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Tobacco cessation interventions for young people

  1. Alan Stanton1,
  2. Gill Grimshaw2,*

Editorial Group: Cochrane Tobacco Addiction Group

Published Online: 23 AUG 2013

Assessed as up-to-date: 31 JUL 2013

DOI: 10.1002/14651858.CD003289.pub5


How to Cite

Stanton A, Grimshaw G. Tobacco cessation interventions for young people. Cochrane Database of Systematic Reviews 2013, Issue 8. Art. No.: CD003289. DOI: 10.1002/14651858.CD003289.pub5.

Author Information

  1. 1

    Heart of England Foundation Trust, Shirley, UK

  2. 2

    Warwick Medical School, Medical Teaching Centre, Coventry, UK

*Gill Grimshaw, Medical Teaching Centre, Warwick Medical School, University of Warwick, Coventry, CV4 7AL, UK. gill@gillgrimshaw.com.

Publication History

  1. Publication Status: New search for studies and content updated (no change to conclusions)
  2. Published Online: 23 AUG 2013

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Characteristics of included studies [ordered by study ID]
Aveyard 2001

MethodsCountry: UK
Setting: Schools in West Midlands
Study design: Cluster randomized controlled trial. Schools sampled with probability in proportion of size of year group. Combined prevention/cessation trial


ParticipantsParticipants: 1089 adolescent smokers (defined as >=1 cpw) (I 547; C 542)
Age range: 13-14 yrs
Criteria for inclusion: Inclusion was at level of school; 89 schools approached, 53 agreed to participate. Data extracted for this cessation review based on all pupils in year 9 who smoked >=1 cpw
Follow-up method: Questionnaire to all students
Inducements to enter study: None
Pre-study Smoking status assessment: self reported
Post study smoking status assessment: self reported
Significant demographic differences between arms of trial: None apparent in published data*


InterventionsIntervention: Computer 'expert system' designed to diagnose stage of change and deliver material tailored to individual. Six sessions, 2 per term, 1 class-based (tutor training mandatory) and one computer-based delivered over period of school year (3 school terms per year in UK).
Theoretical basis of intervention: Psycho-social intervention based on transtheoretical model of stages of change.
Control: Control schools received health education as delivered locally at that time; in addition teachers received 3 lesson plans plus handouts but no specialist training or record of what was delivered.
Theoretical basis of control: Normal local practice


OutcomesMeasurement: 7-day and 30-day PPA (supplied by author); Follow-up periods >3m, 12m (mean length of follow-up 359 (I) to 347 (C) days) and 24m from start of study, equivalent to 4m and 16m after end of intervention.
Verification: None
Losses to follow-up: 11% (I) and 10.7% (C) @ 12m; 14% (I) and 16.9% (C) @ 24m (additional data from authors).


Notes7- and 30-day abstinence at 12 & 24m provided by author based on pupil reporting as quitting AND abstinent for stated period as opposed to not smoking for stated period. The latter is basis for results given in this review.
Tested sensitivity of questionnaire kappa 0.87 (0.7-1.00) bias would be towards positive result so ascertainment unlikely to affect validity


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low riskComputer-generated block randomization, balanced by class size

Allocation concealment (selection bias)Low riskComputerised and anonymous

Blinding of participants and personnel (performance bias)
All outcomes
Unclear riskNot specified

Blinding of outcome assessment (detection bias)
All outcomes
Low riskNo biochemical validation, but follow-up surveys anonymised (identified only by ID number) and delivered by trained personnel in 'examination' setting, differential misreport judged to be unlikely

Incomplete outcome data (attrition bias)
All outcomes
Low riskAnalyses tested all models of losses to follow-up

Other biasUnclear riskFidelity of implementation for controls unclear

Brown 2003

MethodsCountry: USA
Setting: Psychiatric hospital, Providence RI
Study design: Randomized controlled trial


ParticipantsParticipants: 191 patients (I 116 ; C 75), 62.3% female, ethnicity 94.8% white
Age range: 13-17 year olds, mean 15.4 yrs
Criteria for inclusion: at least 1 cpw for previous 4 weeks, 64% daily smokers, on average smoking for 3.6 years (additional data from authors)
Follow-up method: Telephone questionnaire
Inducements to enter study: Gift certificates to local mall, escalating in value, on completion of each phase
No significant demographic differences between arms of trial.
Other: Participants were prohibited from smoking during hospital stay (mean length 9 days)


InterventionsIntervention: Motivational interviewing given in 2 sessions of 45 mins plus relapse prevention manual and self help pamphlet
Control: Brief advice session plus self-help pamphlet


OutcomesMeasurement: 7-day PPA; follow-up period/s >3m, 6m, 12m
Pre-study smoking status assessment: Modified Fagerstrom, mean 4.9 (±1.82)
Post study smoking status assessment.
Verification: Salivary cotinine and CO
Losses to follow-up: At 6m 8%; at 12m 9%


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear risk"The assignment of cohorts to treatment condition was determined randomly before the initiation of the study," method of sequence generation not specified

Allocation concealment (selection bias)High riskAllocation based on time of admission. "Between cohorts, no recruitment occurred until study participants from the previous cohort had been discharged from the hospital."

Blinding of participants and personnel (performance bias)
All outcomes
Unclear riskNot specified, not clear if other hospital personnel blind to treatment assignment

Blinding of outcome assessment (detection bias)
All outcomes
Low riskBiochemical validation used at 1, 6 and 12m follow-up visits

Incomplete outcome data (attrition bias)
All outcomes
Low risk91% followed up at 12 months, "rates of missing data were not significantly different across motivational intervention and brief advice conditions."

Chan 1988

MethodsCountry: USA
Setting: University dormitories, Richmond VA
Study design: Cluster controlled trial; Only two arms contribute (Health Risk Assessment with and without feedback) as single control group not measured at beginning and end of study.


ParticipantsParticipants: 40 University freshmen smokers
Age range: 17-18
Criteria for inclusion: 50% of freshman randomly selected.
Follow-up method: Computer scored Health Risk Appraisal [HRA] Questionnaire
Inducements to enter study: None
Pre-study Smoking status assessment: self assessment
Post study smoking status assessment: self assessment verified by resident advisor with option to modify
No significant demographic differences between arms of trial.


InterventionsFour-arm trial:
1) Health Risk assessment [HRA] at start of study, feedback on results and second assessment 1 year later (n=23)
2) HRA at start of study and HRA at end (n=17)
3) HRA at start only (no end of study data collection on smoking behaviour)
4) HRA at end only (no baseline data collection on smoking behaviour)
Only arms (1) and (2) compared for this review


OutcomesMeasurement: self-reported 30-day PPA; Follow-up period/s >3m; approx 9m.
Verification: resident advisor's report, with no biochemical validation


NotesAs data collection on control groups was not done before and after, only one comparison can be made. Authors noted that there was a risk of contamination between groups.


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)High riskFour dormitories assigned to four conditions, method of assignment not specified

Allocation concealment (selection bias)High riskAssignment based on dormitory, allocation concealment not specified

Blinding of participants and personnel (performance bias)
All outcomes
Unclear riskNot specified

Blinding of outcome assessment (detection bias)
All outcomes
Low riskNo biochemical validation used but verification obtained through resident advisor's report, "who interacted with the freshman on a daily basis," differential misreport unlikely.

Incomplete outcome data (attrition bias)
All outcomes
Low risk6 students who withdrew from university excluded from final denominator, 100% follow-up for all others

Other biasUnclear riskContamination possible: "...informational exchange among students in different groups might still occur."

Colby 2005

MethodsCountry: USA
Setting: Hospital outpatient or emergency departments in Rhode Island
Study design: Randomized controlled trial


ParticipantsParticipants: 85 adolescents (43 I; 42 C)
Age range: 14 -19 yrs
Criteria for inclusion: reported daily smoking for previous 30 days
Follow-up method: Timeline Follow Back to inform structured interview
Inducements to enter study: US$10 gift voucher for completion.
Pre-study Smoking status assessment: self reported cpd in last 30 days
Post study smoking status assessment: verified self-reported smoking pattern in last 90 days
Significant demographic differences between arms of trial: Not reported


InterventionsIntervention: 35 minute personal motivational interview with 1 week follow-up phone call of 15- 20 minutes
Theoretical basis of intervention: Motivational enhancement
Control: 5 minute advice interview plus pamphlet and brief phone call 1 week after visit
Theoretical basis of control:Brief Intervention


OutcomesMeasurement: 7-day PPA; follow-up periods: >3m, 6m.
Verification: CO and cotinine
Losses to follow-up: 20% at 6 months


NotesAuthor of study considers little confounding amongst extensive array of variables
High withdrawal and non-recruitment rate.


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear risk"Randomly assigned," method of sequence generation not specified

Allocation concealment (selection bias)Unclear riskNot specified

Blinding of participants and personnel (performance bias)
All outcomes
Unclear risk"The research assistants in this study were blind to treatment condition," unclear if participants in control group knew of intervention being provided.

Blinding of outcome assessment (detection bias)
All outcomes
Low riskBiochemical validation used

Incomplete outcome data (attrition bias)
All outcomes
Low riskParticipants lost to follow-up counted as smokers, 80% of participants followed up at 6m, no significant difference in loss to follow-up between treatment groups

Greenberg 1978

MethodsCountry: USA
Setting: High schools
Study design: Randomized controlled trial


ParticipantsParticipants: Open recruitment, first 100 recruited
Age range: 14 -16 (Grades 9-11 )
Criteria for inclusion: All participants smoked at least 5 cpd
Inducements to enter study: Half a unit credit for experimental groups
Pre-study Smoking status assessment: self report
Post study smoking status assessment: self report


InterventionsIntervention: Group A (n=25) received 'scare' education; Group B (n=25) 'fact'-based education, Group C (n=25) 'attitude' approach using affective strategies. All classes took place in weekly sessions over 7 weeks.
Theoretical basis of intervention: Affective teaching strategies consistent with theoretical development at time of trial
Control: Control group (n=25) spent time in study hall without any active intervention


OutcomesMeasurement: PPA ['no longer smoked']; follow-up period/s >3m, 5m after end of intervention. Intervention lasted 7 weeks, so endpoint 6-7m post-baseline.
No biochemical verification.
Losses to follow-up: 22% at final follow-up.
Results:
All ORs calculated. Quitters: Group A 3 students; Group B 0 students; Group C 6 students and control 1 student
Overall OR for aggregated quitting = 3.27 (0.39 - 27.21)
Group A vs control OR = 3.27 (0.32-33.84)
Group B vs control OR = 1(0)
Group C vs control OR = 7.58 (0.84 - 68.46) (displayed in analyses


NotesNo power calculations evident from paper but published in 1978 so report consistent with current practice.
Lack of information regarding allocation and potential confounding in this study.


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear riskNot specified, not clear if randomization used

Allocation concealment (selection bias)High risk"The subjects were divided into four equal groups... designated to meet during four different daily class periods," suggests allocation was not concealed

Blinding of participants and personnel (performance bias)
All outcomes
Unclear riskNot specified

Blinding of outcome assessment (detection bias)
All outcomes
High risk"An attempt was made to validate the self-report data by asking about smoking behaviour in two different parts of the questionnaire by two differently-worded questions." Self-reported smoking status used, differential misreport possible.

Incomplete outcome data (attrition bias)
All outcomes
Low risk78% followed up at 5m, rates similar in each group

Hoffman 2008

MethodsCountry: USA
Setting: 7 Public high schools in Montgomery county, Maryland
Study design: Cluster randomized controlled trial randomized at level of school


ParticipantsParticipants: 105 adolescent smokers
Age range: 14 - 18
Criteria for inclusion of school: Not currently participating in any other smoking cessation interventions
Criteria for inclusion of students: Those who had smoked ≥1 cpd for 30 days and were willing to attend 6 sessions plus follow-up at 1 year.
Follow-up method: Project team interviews face-to- face and by telephone
Inducements to enter study: None
Pre-study Smoking status assessment: self-reported 30-day smoking status
No significant demographic differences in participants in arms of study


InterventionsIntervention: ASCENT programme included "cognitive behavioural therapy" tailored to stage of change (TTM), a student workbook, role play, discussion and games and video all delivered over 6 sessions of 1 hour per week over 6 weeks. However, as intervention was delivered to a group, TTM component not strictly applied.
Theoretical basis of intervention: TTM and CBT
Control: Normal teaching and information giving within school


OutcomesMeasurement: Quitting defined as no smoking in 24 hrs prior to interview.
Follow-up periods: 3m, 1 year.
Verification: Saliva cotinine attempted but either kits failed or students didn't provide sample.
Losses to follow-up: 16% at 12 months


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear risk"Schools were randomized," method of sequence generation not specified

Allocation concealment (selection bias)Low riskSchools randomized, not participants. Students recruited prior to status of school being known.

Blinding of participants and personnel (performance bias)
All outcomes
Unclear riskNot specified

Blinding of outcome assessment (detection bias)
All outcomes
High riskCotinine collected but not used, previous studies have found high misreport in adolescents even when aware biochemical validation would be used, hence misreport cannot be ruled out for this study

Incomplete outcome data (attrition bias)
All outcomes
Low risk16% loss to follow-up at 12m, "A series of attrition analyses examining both the 30-day and 12-month follow-up data indicated no differential loss of youth by condition, sex, racial group or having plans to quit in the next 30 days."

Hollis 2005

MethodsCountry: USA
Setting: 7 pediatrics and family practice departments in HMO medical centres in Oregon and Washington state.
Study design: Randomized controlled trial (prevention and cessation). Blocked randomization method, using sealed envelopes.


ParticipantsParticipants: 448 adolescent smokers selected from 2524 recruits attending clinic appointments.
Age range: 14 - 17
Criteria for inclusion: Those who were willing to stay after consultation at clinic and had no intention of leaving geographical area within 1 year.
Follow-up method: Mailed questionnaires and telephone interviews
Inducements to enter study: None
Pre-study Smoking status assessment: self-reported 30-day smoking status
Non-significant demographic differences between arms of trial at level of P < 0.05 except for small difference in positive at depression screen (P < 0.01)


InterventionsIntervention: 3 sequential interventions plus maximum of 2 boosters:
(1) Clinical message encouraging quitting or not starting, (2) 10-12 minute individual multi-media interactive computer-delivered expert system tailored to stage of change of individual (3) 3-5 mins of motivational counselling by trained health counsellors. Boosters were delivered at clinic attendance (computer programme and motivation counselling) or by telephone (motivational counselling only). Repeated attempts were made to deliver boosters.
Theoretical basis of intervention: Prompts to clinicians to give brief advice, TTM and motivational interviewing
Control: Dietary advice (5-a-day fruit and vegetables); Theoretical basis of intervention: Brief advice - 3-5 mins motivational counselling


OutcomesMeasurement: 30-day PPA; Follow-up periods: >3m, 1 year and 2 years.
No verification.
Losses to follow-up: 6% at 12 months and 12% at 24 months


NotesThis systematic review uses definition of smoking of 1 cpw for at least 6m to define a regular smoker. Hollis et al confirm that their definition of 'smokers' most closely fits this criterion.
We have only used the data for smokers, although the trial included separate smoking uptake prevention results.


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear risk"blocked over time and stratified according to medical centre and 30-day cigarette smoking status," method of sequence generation not specified

Allocation concealment (selection bias)Low risk"Study staff members not involved in recruitment or randomization printed the stratified allocation assignments on index cards and concealed the cards in envelopes."

Blinding of participants and personnel (performance bias)
All outcomes
Unclear riskNot specified

Blinding of outcome assessment (detection bias)
All outcomes
High riskAssessor blinded, but no biochemical validation used. Differential misreport possible.

Incomplete outcome data (attrition bias)
All outcomes
Low riskLoss to follow-up at 2y higher in treatment group (14.3%) than in control group (10.1%). Six types of analyses to model missing data, including ITT analysis in which participants lost to follow-up counted as smokers. "Conclusions were largely consistent among the various missing-data procedures."

Horn 2007

MethodsCountry: USA
Setting: Suburban Emergency Department
Study design: Randomized controlled trial


ParticipantsParticipants: Presenting for care at an ED (excluding those not competent or in police custody) 40/75 in Intervention and 35/75 in control arm
Age range:14-17
Criteria for inclusion: Reported smoking within 30 days, willing to participate and providing written consent
Follow-up method: Phone calls
Inducements to enter study: None
Pre-study Smoking status assessment: mFTQ and CO


InterventionsIntervention: 5 stage Motivational Interviewing (1) screening (2) Tailored interview of 15-30 mins (3) stage sensitive homework book (4) handwritten postcard within 3 days (5) Motivational phone calls at 1/12, 3/12 and 6/12.
Theoretical basis of intervention: Motivational Interviewing
Control: Brief intervention including screening, generic advice giving (2 mins) referral to information line
Theoretical basis of control: Normal care


OutcomesMeasurement: Self report at 6 months. 1 person quit in both intervention and control.
Verification. None


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low riskComputerized: "sequentially numbered...as sorted by the SAS random number function"

Allocation concealment (selection bias)Low riskAllocation concealed in manila study envelope, single pile, sequentially numbered. "Each randomized manila folder contained either the MTI or the BA protocol set of equal size and weight."

Blinding of participants and personnel (performance bias)
All outcomes
Unclear risk"Each provider was blinded during the initial screening." No further blinding reported.

Blinding of outcome assessment (detection bias)
All outcomes
Low riskNo biochemical validation used, different levels of intensity between groups, differential misreport possible, however, only 1 participant in each group reported abstinence so outcome unlikely to have been affected by detection bias.

Incomplete outcome data (attrition bias)
All outcomes
High risk60% intervention and 65% control lost to follow-up at 6m. Authors state: "follow-up found low retention rates, presenting potential biases in our data" though "no significant differences between absent and present teenagers at 6-month follow-up were observed."

Joffe 2009

MethodsCountry: Maryland, USA
Setting: 4 High schools (I: 2; C:2)
Study design: Randomized controlled trial with individuals randomised within schools, schools allocated in balanced blocks


ParticipantsParticipants: 193 students (I: 104; C: 104).
Age range: 14-18 years, mean 15.9
Criteria for inclusion: self-report of smoking AND expressed willingness to quit
Follow-up method: Self reports and salivary cotinine verification of smoking status

Inducements to enter study: Sessions conducted over lunch which was provided plus "modest incentives"

Verification of smoking status: None

Pre study smoking status assessment: self reports, age first smoked and "nicotine dependence".
Significant demographic differences between arms of the trial: slight imbalance in ethnicity, age, nicotine dependence and quit attempts

Post study smoking status assessment: Self report and salivary cotinine


InterventionsIntervention: "Kickin' Butts": 15 lunch time sessions of 25/30 mins (compared to 8 x 50 mins sessions of original intervention)
Theoretical basis of intervention: Programme used that of Adelman 2000 (see Excluded studies for references). Programme design "guided by information gathered in preliminary focus groups, directed interviews, and current teen and adult smoking cessation programs."
Control: Brief Intervention of one session with pamphlets


OutcomesMeasurement: 30 day point prevalence abstinence
Follow-up periods: 6 months and 12 months
Verification: Self reporting verified by salivary cotinine
Losses to follow-up: 69% followed up at 6 months and 62% at 12 months


NotesNew for 2013.

Same study also evaluated a NoT intervention, see NoT MD 2009


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear riskBlock randomization, no information given on sequence generation

Allocation concealment (selection bias)Unclear riskNot specified

Blinding of participants and personnel (performance bias)
All outcomes
Unclear riskNo blinding of personnel, not clear if participants knew what intervention other group was receiving

Blinding of outcome assessment (detection bias)
All outcomes
Low riskBiochemical validation used

Incomplete outcome data (attrition bias)
All outcomes
Low riskNo significant difference between groups in terms of percentage lost to follow-up. Authors conducted two ITT analyses, one treating those lost to follow-up as smokers.

Kelly 2006

MethodsCountry: Australia
Setting: Three state high schools in Brisbane
Study design: Randomized controlled trial. Students referred into trial as a result of violation of smoking policy.


ParticipantsParticipants: 56 students (34% female)
Age range: 14-16 years with parental consent
Criterion for Inclusion: Violation of school smoking policy
Pre study status assessment: Modified Fagerstrom 3.6±1.4, consumption ∼50 cpw
follow-up method: 1,3 and 6 month self-reported tobacco use
Inducements: Not stated
Pre-study smoking status assessment: self reporting


InterventionsIntervention: Motivational Interview with trained interviewer of 1 hour duration with information targeted directly at reported experiences of smoking additional reading following interview
Control: Standard care interview of 1 hour duration and within interview use of a "quit kit" plus review of general literature on effects of smoking within interview time.


OutcomesMeasurement: 30 day PPA no verification
follow-up periods 3/12 and 6/12
Losses to follow-up: 25% at 6 months assumed relapsed.


NotesModerate differences in intervention and control groups but not regarded as significant to outcomes of study


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear risk"Randomly assigned," no further information provided

Allocation concealment (selection bias)Unclear riskNot specified

Blinding of participants and personnel (performance bias)
All outcomes
Unclear riskNot specified, not clear if participants knew what interventions the other group was receiving

Blinding of outcome assessment (detection bias)
All outcomes
High riskNo biochemical validation used, interventions delivered by author, differential misreport possible

Incomplete outcome data (attrition bias)
All outcomes
Low riskSimilar loss to follow-up in both groups (6/30 intervention, 8/26 control), participants lost to follow-up counted as smokers in ITT analysis. "To test for attrition bias, differences between attritors and nonattritors were tested using one-way ANOVAs... There were no significant differences on any variables except mother's occupational status."

Killen 2004

MethodsCountry: USA
Setting: Nine continuation high schools in San Francisco, CA
Study design: Randomized controlled trial. Quality of allocation concealment confirmed by author.


ParticipantsParticipants: 211 smokers.
Age range: 15-18 years
Criteria for inclusion: currently smoked at least 10 cpd, for at least 6m, with >1 quit attempt and a score of at least 10 on modified FNTQ.
Inducements to enter study: US$50 at end of treatment and US$50 for completing 6m assessment.
Pre-study Smoking status assessment: mean cpd 15 and mean FNTQ score 16.6
No significant demographic differences between arms of trial.
Health screening was conducted; those screened positive for depression (clinical diagnosis) were excluded


InterventionsIntervention: 8 weeks of tailored NRT patch therapy plus 150mg SR bupropion tablet (for 8 weeks from quit date) and relapse prevention
Theoretical basis of intervention: Pharmacological plus group work (theoretical basis not given)
Control: 8 weeks of tailored NRT patch therapy plus placebo tablet. (for 8 weeks from quit date)


OutcomesMeasurement: 7-day PPA; follow-up periods: >3m, 6m.
Verification: CO monitoring (below 9ppm) and saliva cotinine (below 20 ng/ml) at 6m; adherence to bupropion measured at 5 weeks
Losses to follow-up: 36% at 6m.


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear riskRandomization method not described.

Allocation concealment (selection bias)Unclear risk"Assignment to treatment condition was double blind," no further information provided.

Blinding of participants and personnel (performance bias)
All outcomes
Low risk"Double blind," no further information provided, but placebo used and treatment effect not found, performance bias judged to be unlikely

Blinding of outcome assessment (detection bias)
All outcomes
Low riskBiochemically validated abstinence

Incomplete outcome data (attrition bias)
All outcomes
Low risk38% bupropion & 35% placebo lost at 6 months, included in analysis.

Lipkus 2004

MethodsCountry: USA
Setting: 11 shopping malls and an amusement park in North Carolina, South Carolina, Gerogia and Tennessee
Study design: Randomized controlled trial


ParticipantsParticipants: 402 adolescents (I 209; C 193)
Age range: 15-18 years old
Criteria for inclusion: ≥1 cigarette within preceding 7 days (mean years smoked 3 ±2, and 10 ±8 cpd)
follow-up: Telephone survey
Inducements to enter study: a movie pass
Pre-study smoking status assessment: Nicotine dependence measured using mFTQ
No significant demographic differences between arms of trial.


InterventionsIntervention: Telephone counselling, self help materials and a video
Theoretical basis of intervention: Eclectic but pre-tested with age-appropriate group and contains elements of CBT and TTM. Telephone counselling used motivational interviewing
Control: Self help materials and a video
Theoretical basis of control: Eclectic, see above


OutcomesMeasurement: 7-day PPA and sustained abstinence (defined as not smoking at both 4m and 8m assessment points); follow-up periods >3m, 8m.
Verification: saliva cotinine at level of >10ng/ml at 4m; self-report only at 8m.
Losses to follow-up: 36% at 8m.
Results: 7 day quitting: 21% (calculated as 44 smokers ) in intervention and 19% (calculated as 37) in control. Sustained quitting 9% (calculated as 19) in intervention arm and 7% (calculated as 14) in control.
ITT for sustained quitting OR =1.279 (0.622 - 2.627)
ITT for 7 day point prevalence OR = 1.124 (0.690 - 1.833)


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear riskRandomized, method not described, stratified by SoC

Allocation concealment (selection bias)Unclear riskNo details given

Blinding of participants and personnel (performance bias)
All outcomes
Low riskDue to minimal contact nature of intervention, performance bias unlikely

Blinding of outcome assessment (detection bias)
All outcomes
High riskBiochemical validation done but final outcome figures based on self-report only. High failure to confirm and low response rate.

Incomplete outcome data (attrition bias)
All outcomes
Low risk46% Int & 51% Cont reached at both follow-ups. Losses included as smokers.

Moolchan 2005

MethodsCountry: USA
Setting: Baltimore, MD, by invitation through media advertisements, schools, churches.
Study design: Randomized controlled trial


ParticipantsParticipants: 120 Smokers (I 80, C 40)
Age range: 13-7 years
Criteria for inclusion: Smoking 10 or more cpd for at least 6m and motivation to quit >5 on 10-point integer scale. Only those who were happy to inform parents of smoking status were included.
Follow-up method: interim and final questionnaires and final visit for verification of smoking status
Inducements to enter study: US$90 for baseline and US$135 after final visit/completion
Pre study Status assessment: Mean 18.8 cpd, 'youth appropriate' Fagerstrom mean 7.04
No significant demographic differences between arms of the trial.


InterventionsIntervention: Nicotine patch and gum, and self-help written materials. Two active groups (a) active patch with placebo gum (n=34) (b) active gum with placebo patch (n=46). NRT for both groups was tailored to weight and smoking level. Participants received 11 visits over 12 weeks to receive NRT, and attended 45 minute group CBT session at the end of each visit, + self-help materials. Theoretical basis of intervention: Pharmacological
Control: placebo patch and gum (n=40).


OutcomesMeasurement: 7-day PPA, and 'prolonged' abstinence, i.e. continuous abstinence after a 2 week grace period from end of intervention; Follow-up periods: >3m, 6m.
Verification: CO, salivary cotinine and thiocyanate.
Losses to follow-up: 54%


NotesTimeline for trial was verified with authors.
Adverse event 'profile consistent with that reported for adults'.


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low risk"Randomized ... according to an algorithm held by the National Institute on Drug Abuse Pharmacy, with true replacement of the non-completers".

Allocation concealment (selection bias)Unclear riskNot stated

Blinding of participants and personnel (performance bias)
All outcomes
Unclear riskDescribed as "double-blind, double-dummy", but no further information.

Blinding of outcome assessment (detection bias)
All outcomes
Low riskBiochemically validated abstinence

Incomplete outcome data (attrition bias)
All outcomes
Low riskLosses to follow-up were included as failures for cessation. Losses fully reported.

Muramoto 2007

MethodsCountry: Arizona, USA
Setting: Community recruitment
Study design: Double-blind randomized controlled trial with two treatment arms.


ParticipantsParticipants: 312 smokers (I 209; C 103)
Age range:14 -17 years
Criteria for inclusion: Smoking at least 6 cpd & exhaled CO≧10ppm & at least two prior quit attempts & no major psychiatric diagnosis
Follow-up method: Telephone visit at 12 weeks and 26 weeks post target quit date.
Inducements to enter study: None
Pre-study smoking status assessment: Self report previous 90 days, mFTQ and CO verification


InterventionsIntervention 1: Buproprion SR 300 mg/day in blister cards
Intervention 2: Buproprion SR 150 mg/day in blister cards
Theoretical basis of intervention: Pharmacological Phase III trail including "standardised brief individualised counselling" at each visit.
Control: 0 mg/day placebo tablet identical to active tablets and blister packed
Theoretical basis of control: Pharmaceutical


OutcomesMeasurement: Self reports of 7 day point prevalence (30 day PPA stated as an outcome in paper but figures not given, not obtainable from author) at 26 weeks
Verification: Exhaled CO at 26 week visit


Notes300 mg versus placebo displayed in analyses. 150 mg had fewer quitters than control (2/105, vs 6/103, RR 0.33 95% CI 0.07, 1.58). Losses to follow-up: 19/104 in 300 mg, 31/105 in150 mg, 19/105 in control


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low risk"Active study medication and identical-appearing placebo were prepackaged into 3 sets of identical-appearing blister cards in accordance with a computer-generated randomization list."

Allocation concealment (selection bias)Low risk"... a research assistant assigned the subject the next treatment number (and associated blister cards) in sequence."

Blinding of participants and personnel (performance bias)
All outcomes
Low risk"Study subjects and researchers remained blind to treatment group assignment throughout the study," identical appearing placebo used (see above)

Blinding of outcome assessment (detection bias)
All outcomes
Low riskBlinded and biochemically validated abstinence

Incomplete outcome data (attrition bias)
All outcomes
Low riskSlightly higher lost to follow-up/ declined further participation in placebo group (30%) than active arms (18%). ITT analysis.

Myers 2005

MethodsCountry: USA
Setting: Outpatients in substance abuse programme in Southern California
Study design: Non-randomized controlled trial


ParticipantsParticipants: 54 Smokers: (I 26; C 28 [on waiting list])
Age range: 13-18 years, mean 16.1 yrs
Criteria for inclusion: Reported weekly smoking, smokers were required to attend treatment but participation in the outcome study was voluntary
Follow-up method: questionnaires and visit for verification of smoking status/
Inducements to enter study: Gift certificates US5 for baseline, US5 for 3m follow-up and US$45 on completion at 6m.
Pre study Status assessment: Mean 7.96 cpd in intervention group and 10.0 in control group, modified Fagerstrom scores of 3.85 in intervention group and 3.68 in control group
Post study smoking status assessment: Teen Smoking Questionnaire
Significant demographic differences between arms of the trial: Authors claim statistically significant difference only in % of pre-contemplators, although we note that the control group had fewer girls than the intervention group (14% vs 31%).


InterventionsIntervention: Motivational enhancement delivered in 6 sessions of 1 hour each in groups.
Theoretical basis of intervention: Eclectic with CBT and motivational enhancement
Control: waiting list


OutcomesMeasurement: 7-day and 90-day PPA and Time Line follow back; Follow-up periods: >3m, 6m.
Verification: CO and salivary cotinine, and parental corroboration
Losses to follow-up: 33%


NotesAdditional information from author


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)High risk"We used a sequential cohort design whereby conditions were successively switched between SRC (intervention) and WL (waiting list) within each site."

Allocation concealment (selection bias)High riskSee above

Blinding of participants and personnel (performance bias)
All outcomes
Unclear riskNo information provided, unclear if waiting list participants knew they were being placed on hold to receive treatment

Blinding of outcome assessment (detection bias)
All outcomes
Low riskAbstinence biochemically validated

Incomplete outcome data (attrition bias)
All outcomes
Low risk67% completed 6m follow-up. "Attrition analyses... indicated no significant differences on demographic or baseline smoking variables between missing and included participants at any
follow-up assessment time point. Chi-square analyses indicated no differential attrition by treatment condition at any time point."

NoT AL 2008

MethodsCountry: Alabama, USA
Setting: 71 High schools (I: 44; C: 27)
Study design: Randomized controlled trial


ParticipantsParticipants: 400 students (I 192; C 208).
Age range: 16-18 years (subset),
Criteria for inclusion: Willingness to consent and self-report of smoking
Follow-up method: Self reports and verification of smoking status
Inducements to enter study: Originally participants given small value key chains. Later stages of study incentives changed to $5-$20 rising as increasing time from baseline
Verification of smoking status: Salivary cotinine
Pre study smoking status assessment:
Significant demographic differences between arms of the trial: Intervention group had slightly higher nicotine dependence
Post study smoking status assessment:


InterventionsIntervention: NoT Intervention: 1 x 50-minute session once a week for 10 weeks, same-gender small groups (no more 10 in the group) led by same-gender facilitators. Covers motivation, smoking history, nicotine dependence, social, psychological and health consequences of smoking, preparation for quitting, urges and cravings, relapse prevention, stress management, family/peer pressure, healthy lifestyle, nutrition. Four booster sessions offered post-programme at 2 and 4 weeks.
Theoretical basis of intervention: Social cognitive theory
Control: Brief Intervention (mixed gender groups, 5 minutes scripted advice, 10 minutes to describe purpose and answer questions, pamphlets)


OutcomesMeasurement: 7 day & 30 day PPA
Follow-up periods: 6 months and 12 months
Verification: Self reporting with a sub-group verified by salivary cotinine.
Losses to follow-up: 63% at 6 months and 71% at 12 months. Losses to follow-up much higher in Intervention group - 77% vs 49% at 12 months


NotesThe original study included 16-19 year olds. This review uses 7 day PPA data for 16-18 year olds supplied by Investigators. Losses to follow-up given are for 16-19 year old group. Demographic and motivational differences for participants. More difficulty reported in recruiting schools to Intervention Group.


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)High riskNot randomized, pre-post assessment design with comparison.

Allocation concealment (selection bias)High riskDifferent recruitment procedures for intervention and control groups. "Intervention schools were recruited... according to NoT procedures, including endorsement and support of high school administrators, faculty, and staff."

Blinding of participants and personnel (performance bias)
All outcomes
Unclear riskNot specified

Blinding of outcome assessment (detection bias)
All outcomes
Low riskBiochemical validation used

Incomplete outcome data (attrition bias)
All outcomes
High riskDifferential and high losses to follow-up (at 12m, 21% intervention and 34% control available for follow-up).

NoT FL 2001

MethodsCountry: USA
Setting: 40 high schools in Florida
Study design: Cluster controlled trial. A matching procedure was used 'to better accommodate the community based research partners and challenges they faced (e.g. local schools who already had NoT in place )'.


ParticipantsParticipants: 423 Smokers in 40 schools (I 249; C 174)
Age range: 14-19 years,mean approx 16 years.
Criteria for inclusion: self-reported smoking at least 5cpd.
Follow-up method: self reports and verification of smoking status
Pre study smoking status assessment: Approx 11.7 cpd on weekdays and 18.2 cpd on weekends. mFTQ of around 6.0 (reported for each arm of trial)
Significant demographic differences between arms of the trial: Interevention group had slightly higher nicotine dependence.


InterventionsIntervention: NoT Intervention: 1 x 50-minute session once a week for 10 weeks, same-gender small groups (no more 10 in the group) led by same-gender facilitators. Covers motivation, smoking history, nicotine dependence, social, psychological and health consequences of smoking, preparation for quitting, urges and cravings, relapse prevention, stress management, family/peer pressure, healthy lifestyle, nutrition. Four booster sessions offered post-programme at 2 and 4 weeks.
Theoretical basis of intervention: Social cognitive theory
Control: Brief Intervention (mixed gender groups, 5 minutes scripted advice, 10 minutes to describe purpose and answer questions, pamphlets)


OutcomesMeasurement: 1-day or longer PPA; Follow-up periods: >3m, 6m (mean 7.3m from baseline)
Verification: CO
Losses to follow-up: approx 50%


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)High riskNot randomized, researchers select schools from waiting list. "The study used a "matched" design. Each year, 10 NoT schools were selected and then a BI school was matched to each NoT school..."

Allocation concealment (selection bias)High riskSee above

Blinding of participants and personnel (performance bias)
All outcomes
Unclear riskNot specified

Blinding of outcome assessment (detection bias)
All outcomes
Low riskBiochemical validation used

Incomplete outcome data (attrition bias)
All outcomes
High riskLarge and differential rate lost to follow-up: 42% control, 59% intervention.

NoT MD 2009

MethodsCountry: Maryland, USA
Setting: 4 High schools (I:2 and C:2)
Study design: Randomized controlled trial with individuals randomised within schools, schools allocated in balanced blocks


ParticipantsParticipants: 194 students (I: 92; C: 102)
Age range: 14-18 years, mean 15.9
Criteria for inclusion: self-report of smoking AND expressed willingness to quit
Follow-up method: self report & salivary cotinine verification

Inducements to enter study: Sessions conducted over lunch which was provided plus "modest incentives"

Verification of smoking status: None

Pre study smoking status assessment: self reports, age first smoked and "nicotine dependence".
Significant demographic differences between arms of the trial: slight imbalance in ethnicity, age, nicotine dependence and quit attempts

Post study smoking status assessment: Self report and salivary cotinine


InterventionsIntervention: Modified NoT Intervention: 20 lunch time sessions of 25/30 mins (compared to 5 x 50 mins sessions of other NoT trials)
Theoretical basis of intervention: Social cognitive theory
Control: Brief Intervention of one session with pamphlets


OutcomesMeasurement: 30 day point prevalence abstinence measured
Follow-up periods: 6 months and 12 months
Verification: Self reporting verified by salivary cotinine
Losses to follow-up: at 6 months and at 12 months


NotesNew for 2013. Clarification of data and details of incentives sought from authors but not received at time of publication.

Same study also evaluated an alternative intervention, see Joffe 2009.

Modified NoT: entered as NoT since basis of intervention same but timescale of delivery modified.


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear risksee Joffe 2009

Allocation concealment (selection bias)Unclear risksee Joffe 2009

Blinding of participants and personnel (performance bias)
All outcomes
Unclear risksee Joffe 2009

Blinding of outcome assessment (detection bias)
All outcomes
Low risksee Joffe 2009

Incomplete outcome data (attrition bias)
All outcomes
Low risksee Joffe 2009

NoT NC 2002

MethodsCountry: USA
Setting: 10 high schools (5 matched pairs) in North Carolina
Study design: Cluster controlled trial. Intervention schools were allocated where there were NoT facilitators trained to deliver the intervention already present in the school.


ParticipantsParticipants: 122 smokers (I 61; C 61)
Age range: 14-19 years, mean approx 16 years. 93.4% white, 56% female.
Criteria for inclusion: self-reported smoking at least 5cpd.
Follow-up method: self reports and verification of smoking status.
Pre study smoking status assessment: Approx 13.3 cpd on weekdays and 19.4 cpd on weekends. Modified Fagerstrom score showed them 'highly addicted'


InterventionsNoT intervention with Brief Intervention as control. See NoT Florida for details.


OutcomesMeasurement: 1-day or longer PPA; Follow-up periods: >3m, 6m, 15m.
Verification: CO < 9 ppm.
Losses to follow-up: approx 50% at 15m.


NotesITT data used.
End of programme, if including booster sessions, is around 6m. OR calculated from trial report.


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)High riskMatched but not randomized

Allocation concealment (selection bias)High riskNot randomized. Authors state, "Notably, the matching procedure does not account for possible confounders that might occur because the NoT schools chose to participate rather than being
randomly assigned to either a treatment or comparison group." Serious flaw and risk of confounding by picking intervention schools where already 'trained to administer' intervention in past (acknowledged).

Blinding of participants and personnel (performance bias)
All outcomes
Unclear riskNot specified

Blinding of outcome assessment (detection bias)
All outcomes
Low riskBiochemical validation used at 3 and 6m follow-ups, "across the 3-month and 6-month observations, there was high agreement between self-report and carbon monoxide-validated quit rates"

Incomplete outcome data (attrition bias)
All outcomes
Unclear riskNumber lost to follow-up not reported (report aggregates attrition from multiple studies). Overall, authors report "There were no significant differences in the attrition rate for NoT (22.5% absent) and BI (18.5% absent) groups, leaving an overall follow-up rate of approximately 80%."

NoT WV 2004

MethodsCountry: USA
Setting: 10 high schools (5 matched pairs) in North Carolina
Study design: Cluster controlled trial. Intervention schools were allocated where there were NoT facilitators trained to deliver the intervention already present in the school.


ParticipantsParticipants: 136 smokers (I 63; C 73)
Age range: 14-19 years, mean approx 16 years. 93.4% white, 56% female.
Criteria for inclusion: self-reported smoking at least 5cpd.
Follow-up method: self reports and verification of smoking status.
Pre study smoking status assessment: Approx 13.3 cpd on weekdays and 19.4 cpd on weekends. Modified Fagerstrom score showed them 'highly addicted'


InterventionsNoT intervention with Brief Intervention as control. See NoT Florida for details.


OutcomesMeasurement: 1-day or longer PPA; Follow-up periods: >3m, 6m, 15m.
Verification: CO < 9 ppm.
Losses to follow-up: approx 52% at 15m.


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)High riskMatched, not randomized

Allocation concealment (selection bias)High riskNot randomized. Serious flaw and risk of confounding by picking intervention schools where already 'trained to administer' intervention in past (acknowledged).

Blinding of participants and personnel (performance bias)
All outcomes
Unclear riskNot specified

Blinding of outcome assessment (detection bias)
All outcomes
Low riskBiochemical validation used at 3 and 6m follow-ups, "across the 3-month and 6-month observations, there was high agreement between self-report and carbon monoxide-validated quit rates"

Incomplete outcome data (attrition bias)
All outcomes
Unclear riskApprox 50% available at 12m follow-up but reports on multiple studies, rates of dropout not specified for this particular site

Other biasHigh riskNon-significant difference at 15m caused by doubling of control quit rate between 6m and 15m. This may be partly attributable to Master Settlement Agreement funding of US$5.8 million administered across the state for prevention activities, which confounded the background rate.

NoT WV 2011

MethodsCountry: United States
Setting: 99 Public High schools in West Virginia
Study design: Cluster controlled trial. Intervention schools were allocated to either NoT alone or NoT plus a physical activity programme. This enabled comparison of NoT with NoT plus FIT.


ParticipantsParticipants: 233 participants (I 170, C 63). NoT alone had 90 in intervention group and NoT plus FIt had 80 in Intervention group
Age range: 14 -19yrs
Criteria for inclusion: ≥ 1 day of smoking in last 30 days
Inducements to enter study: None
Pre-study smoking status assessment: Self reports
Post study smoking status assessment: Self reports plus breath CO at 3 months but self reported only at 6 months


InterventionsNoT intervention with Brief Intervention as control. See NoT FL 2001 for details.

NoT plus FIT participants were given a pedometer and encouraged to keep a log of steps taken.


OutcomesMeasurement: 7 day point prevalence abstinence at 3 months, self reported quitting at six months
Biochemical verification: breath CO at 3 months

Losses to follow-up: > 60% of participants retained


NotesNew for 2013. Although results analysed as clusters, 21 (out of 40) schools dropped out after randomisation but before study onset due to recruitment and logistics. We note that the abstract gives impression that 7 day PPA is measured at 6 months. However outcome at 6 months is self report only.


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low riskComputer based randomization

Allocation concealment (selection bias)High risk21 out of 40 schools dropped out after randomization but prior to study start, aware of assignments.

Blinding of participants and personnel (performance bias)
All outcomes
Unclear riskNo information specified, unclear if arms knew what other arms were receiving

Blinding of outcome assessment (detection bias)
All outcomes
Low riskBiochemical validation of outcomes

Incomplete outcome data (attrition bias)
All outcomes
Low risk> 60% followed up, participants lost to follow up counted as smokers

Patten 2006

MethodsCountry: USA
Setting: Community-based in three locations; Minnesota, Winsconsin and Conneticut.

Study Design: Randomized controlled trial

Recruitment: Community based recruitment by television commercials, radio, newspaper announcements and flyers in schools and clinics


ParticipantsParticipants: 139 Smokers: (I 70; C 69 )
Age range: 11-18 years, median 16 yrs
Criteria for inclusion: Smoked > 10 cigarettes in previous 30 days, primarily used tobacco, parental consent given
Follow-up method: Clinic visits at 4,8,12,24 and 36 weeks
Pre study Status assessment: Modified Fagerstrom=4.1±1.9, mean cpd 10.1±6

Inducments to enter study: US$10 per visit for weeks 4 to 24 for completed visits, US$20 at week 36.
Post study smoking status assessment: self reports validated with CO measurement
Significant demographic differences between arms of the trial:None


InterventionsIntervention: Stomp out Smokes delivered by home based Internet and using as theoretical base Social (cognitive) Learning theory, health communication and decision-making theories. Access to SOS was available for 24 weeks after enrolment. No clinician contact except during assessment clinic visits

Control: Brief Intervention (office based) developed by American medical Association and delivered by counsellor at four individual weekly sessions

No participants required to set quit dates and pharmacotherapy not provided.


OutcomesMeasurement: 30-day PPA at 24 weeks and 36 weeks.
Verification: Self reports plus CO validation
Losses to follow-up: 33% at week 24 and 43% at week 36


NotesAs intervention was available up to 24 weeks point outcomes taken from 36 weeks as more realistically demonstrating persistence of intervention.


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear risk"Randomly assigned," method of sequence generation not specified

Allocation concealment (selection bias)Unclear riskNo details provided

Blinding of participants and personnel (performance bias)
All outcomes
Low riskDue to nature of intervention any contact likely to be part of intervention, so performance bias unlikely. "Except for the assessment visits, study staff did not have any personal contact with participants."

Blinding of outcome assessment (detection bias)
All outcomes
Low riskBiochemical validation used

Incomplete outcome data (attrition bias)
All outcomes
Low riskThe percentage attending assessment visit in the intervention and control conditions, respectively, was 42 and 53% at 9m. All randomized participants included in ITT analysis which produces more conservative outcome.

Peterson 2009

MethodsCountry: USA
Setting: High Schools in Washington State
Study Design: Matched pair randomized (at school level) controlled trial
Recruitment: Following smoking status baseline survey in all schools smokers were invited to participate in intervention. Non-smokers also invited to preserve confidentiality of students.


ParticipantsParticipants: 782 Smokers: (I 414; C 368 )
Age range: 16-18 years,
Criteria for inclusion: See Notes as restricted subset. Parental consent sought.
Follow-up method: Questionnaire at 12 months from intervention.
Pre study Status assessment: Self-designed four item scale, mean cpd 10.1±6
Inducements to enter study: US$10 per completed post-study questionnaire (US$20 if survey returned at second or third prompt)).
Post study smoking status assessment: self reports .
Significant demographic differences between arms of the trial: Random assignment but Experimental group contained higher proportion of daily smokers (statistically corrected in analysis)


InterventionsIntervention: Complex intervention including quit kit, tailored telephone counselling, supportive website (TTM based) and school-wide cessation health promotion campaign. Specific attributes of teen smoking addressed, e.g. need for privacy, confidentiality and sense of being in control, state of motivation, importance of peer support
Theoretical basis of intervention: TTM, Motivational Interviewing, CBT and social cognitive theory based counselling
Control: Normal school based activity


OutcomesMeasurement: Self reported 6 month continuous abstinence.
Verification: Self reports. No biochemical validation but internal within-questionnaire validity checks on reports of smoking status
Losses to follow-up: 11% at week 52 after intervention


NotesAuthor supplied data on outcomes as inclusion criteria for this review is smoking at least 1 cigarette per week for six months. Whole study included smokers who had smoked at least 1 cigarette in the last 30 days or time since starting. This analysis uses the study subset "current daily smokers at baseline". This is more restrictive than our own criteria and it is this group that is recognised, in the literature, as most likely to be addicted.


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low riskMatched-pair randomization for individual schools, "schools were randomly ordered within each matched pair, and then, one school in each pair was randomly assigned to the experimental or control condition by a computerized coin flip."

Allocation concealment (selection bias)Low riskComputerized coin flip "performed openly, witnessed, and recorded"

Blinding of participants and personnel (performance bias)
All outcomes
Low risk"The tracking and data collection staff were blind to experimental vs. control status at outcome data collection and entry." As control was normal school based activity, performance bias unlikely.

Blinding of outcome assessment (detection bias)
All outcomes
High riskNo biochemical validation used, intervention higher intensity than control, differential misreport possible.

Incomplete outcome data (attrition bias)
All outcomes
Low risk91% control and 87% intervention completed follow-up survey, ITT analysis conducted.

Project EX Russia 2013

MethodsCountry: Russia
Setting: Summer Recreational Camps
Study design: Cluster randomized controlled trial


ParticipantsParticipants: 164 Smokers (I 76, C 88)
Age range: up to 19 years old
Criteria for inclusion: at least one cigarette per week for at least 6 months prior to enrolment
Follow-up method: At 6 months through telephone calls and emails
Pre study Status assessment: Self reported
Inducements to enter study: None
Post study smoking status assessment: Self reported


InterventionsIntervention: Standard Project EX (see Project EX-1 2001)
Theoretical basis of intervention: Complex intervention including CBT and motivational enhancement.
Control: standard care on tobacco use (officially tobacco use not allowed during camp)


OutcomesMeasurement: Self reported
Biochemical verification. None
Losses to follow-up: 34 out of 164 (I=16, C=18)


NotesNew for 2013.


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low risk"experimental pilot trial that involved different youth that rotated through camps. Conditions were nested within camps. Two rotations of unique subject groups of smokers (program and standard care control) through each of five camps provided the means of controlling for campsite by condition"

Allocation decided by coin toss.

Allocation concealment (selection bias)Unclear riskInsufficient detail reported

Blinding of participants and personnel (performance bias)
All outcomes
Low risk"Youth in a given rotation were informed that they would be offered assistance in quitting smoking. However, they were kept blinded to study condition, which was easy considering that totally different cohorts of youth attended the different camp rotations."

Blinding of outcome assessment (detection bias)
All outcomes
High riskIntervention involved face-to-face contact, no biochemical validation of smoking status

Incomplete outcome data (attrition bias)
All outcomes
Low riskLow loss to follow up in both conditions

Project EX-1 2001

MethodsCountry: USA
Setting: 18 Continuation high schools in southern California
Study design: Cluster randomized controlled trial (assigned by block randomization)


ParticipantsParticipants: 335 smokers, recruited by advertising and flyers within each school. 139 in 6 Project EX schools, 120 in 6 Project EX plus SAC schools, 76 in 6 control schools.
Age range: 14-19 yrs Mean age was 16.8 (± 0.8) years.
Criterion for inclusion: used tobacco in last 30 days.
Follow-up method: Questionnaires and telephone for those who had left school
Inducements to enter study: class credits and class release time
Pre-study smoking status assessment: Questionaire. Mean smoking 8.8cpd ( ± 9.3) Modified Fagerstrom scores 30% in range 0-6, 53% in range 7-13 and 17% in range 14-21.
Post study smoking status assessment: questionnaires
No significant demographic differences between arms of trial


InterventionsIntervention: Initially schools split into three arms: (1) Project EX sessions alone (clinic only schools). (2) Project EX plus school community development 'school-as-community' (SAC schools). (3) Control: standard care.
1. Project Ex is 8 sessions or 'clinics' over a 6-week period delivered to groups and developed in trials. Four sessions are preparation for quitting over 2 weeks, and next 4 are weekly during the first month post-quit.
Theoretical basis of intervention: Complex theoretical constructs including motivation interviewing etc, and including games for groups, education and anger management, yoga, weight control, meditation, assertiveness training, role play and relapse prevention.
2. SAC intervention: modelled on Toward No Drug Abuse programme. Student body organised service, recreational and job training functions, and produced a Project newsletter, to enable expression of anti-tobacco attitudes.


OutcomesMeasurement: 30-day PPA; Follow-up periods: >3m, 6m from start of study.
Verification: CO (for 62 students and results adjusted by false quit reporting factor of this group)
Losses to follow-up: 51% in intervention group - 40% of intervention group dropped out during clinics - 42% in control group lost to follow-up. Results:
No difference in outcomes between two intervention arms of trial so authors pooled data and compared, as a single arm with control arm.
Calculated OR based on 17% in intervention = 44 people and 8% in control being 6 people*
Calculated OR = 2.388 (0.976 to 5.841)

Details from authors:


NotesRecruitment in intervention arm was voluntary; 90% of subjects said they had volunteered because they wanted help with quitting


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear risk"Randomized block design procedure," method not specified

Allocation concealment (selection bias)Low riskStudents recruited after schools randomized

Blinding of participants and personnel (performance bias)
All outcomes
Unclear riskNot specified

Blinding of outcome assessment (detection bias)
All outcomes
Low riskBiochemical validation used for 62 students and results adjusted by false quit reporting factor of this group

Incomplete outcome data (attrition bias)
All outcomes
Low riskPer-protocol analysis and ITT analysis yield similar outcomes, "evidence that the study findings are robust despite the relatively high clinic drop-out rate."

Robinson 2003

MethodsCountry: USA
Setting: 18 schools in Memphis, Tennesee
Study design: Randomized controlled trial


ParticipantsParticipants: 316 smokers referred to study by school administrators or parents after violation of school no smoking policy, 261 students (I 169; C 92) followed up so far [2006].
Age range: 13-19 year olds; 64% male.
Follow-up method: Telephone assessment, self-reporting
Inducements to enter study: Fast food coupons, discounts at music stores and money on completion.
Pre-study smoking status assessment: mFTQ
Significant demographic differences between arms of trial: More cases in intervention than control arms because of school wish to have offenders treated.


InterventionsIntervention: 4 x 50-minute sessions behavioural programme, based on STS (Start To Stop) model, of motivational interviews at start of programme and monthly phone calls for 1 year to assess smoking status and give brief support, based on stage of change.
Theoretical basis of intervention: Social influence theory, motivational enhancement, CBT and TTM
Control: Written material at start of study, and monthly phone calls to assess smoking status.


OutcomesMeasurement: 7-day PPA; Follow-up periods: >3m, 12m.
Verification: Attempted for all quitters. Salivary cotinine samples obtained for 18/41 cases, CO initially as a 'bogus pipeline' for some students.


NotesPaper based on incomplete follow-up and denominators unclear so data not shown in comparisons. No evidence of effect detected. We were unable to obtain clarification from authors
Stratified data available on baseline characteristics
Referral to study for violation of school no smoking policy raises issues of consent.


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear riskRandomization at individual level, method not specified

Allocation concealment (selection bias)Unclear riskNot specified

Blinding of participants and personnel (performance bias)
All outcomes
Unclear riskNot specified

Blinding of outcome assessment (detection bias)
All outcomes
Low riskBiochemical validation used (indicating that 50% of those who had reported quitting had falsified smoking status)

Incomplete outcome data (attrition bias)
All outcomes
Unclear risk92% retention but rates in each group not clear

Other biasUnclear riskPossible contamination as unit of allocation was student, so that controls and interventions mixed in same schools, and there was no concealment of allocation.

Sherbot 2005

MethodsCountry: Canada, Nova Scotia
Setting: Intervention introduced into a wider programme set up for young people who had been identified as having substance abuse problems (including drugs, alcohol and gambling but not tobacco).
Study design: Randomized controlled trial


ParticipantsParticipants: 39 young people, 13 in each study group referred onto programme from both urban and rural settings
Age range: 13 - 19 years
Criterion for Inclusion: Enrolled on "Choices Adolescent Treatment Program" and not taking any psychotropic drugs
Inducements: Wait list received 2x $25each and intervention groups 4x $25 each. All completing participants at 7/12 received $25
Follow-up method: Participants contacted by phone or mail
Pre-study smoking status assessment: FTND
Post study smoking status assessment: Self reported quitting & FTND


InterventionsIntervention: Group A - Motivational Enhancement therapy delivered over a period of four weeks at one session per week
Intervention: Group B - Completion of "Quit 4 life" booklet over a period of four weeks at two sessions in the first week, two sessions in the second week, two sessions in the third week, and three sessions in the fourth week
Theoretical basis of intervention: Motivational interviewing
Control: On waiting list


OutcomesSelf reported quitting at 6 months; Group A 5; Group B 1; Control: 2
Losses to follow-up: Overall 10.3%, Group A 2.6%, Group B 2.1%, Group C 2.7%


NotesAll referrals to both programme and this study were voluntary. 100% of those studied also used marijuana. Quitting data not verified and large differences between intervention groups in baseline smoking reports, possibly explained by outliers.


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)High risk'Participants had the opportunity to draw either an “A,” “B,” or “C” to determine which group they were to be in'

Allocation concealment (selection bias)High riskNo possibility of concealment

Blinding of participants and personnel (performance bias)
All outcomes
Unclear riskNot specified but due to nature of intervention, performance bias unlikely

Blinding of outcome assessment (detection bias)
All outcomes
High riskNo blinding reported, no biochemical validation used

Incomplete outcome data (attrition bias)
All outcomes
Low risk4/39 lost at 6 months

Other biasHigh riskLarge differences between intervention groups in baseline smoking reports, possibly explained by outliers.

Woodruff 2007

MethodsCountry: USA, San Diego County
Setting: 14 schools
Study design: Cluster Randomized controlled trial


ParticipantsParticipants: 136 young people volunteering, (I 77 ; C 59)
Age range: 14 years to 19 years
Criterion for Inclusion: volunteering and consented (parents and teenagers) and smoking at least one cigarettes within the last 30 days
Inducements: Participants were asked to complete an an-line survey and paid (sum in brackets) on completion of survey at baseline($5), immediate post intervention ($10), 3 months post completion ($15) and 12 months post completion ($20)
Follow-up method: Completion of on line survey with reminders
Pre-study smoking status assessment: Self reported
Post study smoking status assessment: Self reported quitting


InterventionsIntervention: Web-based virtual reality world based on sky mall with students as avatars and counsellor present as avatar. Information represented as "shops" and galleries and chat possible as more than one student can be "present". Chat texted based at foot of screen. Students also offered one-to-one counselling sessions with Smoking Cessation professional
Theoretical basis of intervention: Motivational interviewing and responses in virtual world based on social cognitive theory
Control: Asked to complete on-line surveys with inducements.


OutcomesSelf reported quitting at one year; Intervention Group: 19 Control: 18
Losses to follow-up: Overall 27.2%, Intervention Group: 32.5%, Control Group: 20.3%


Notes'Effects of clustering were small' so analysis at individual level.


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear riskCluster randomized by school, method not described

Allocation concealment (selection bias)High riskStudents recruited after schools randomized, with different recruitment methods. The two conditions did not differ significantly on demographic data, although a significantly greater proportion of intervention subjects were alternative/continuation high school students. The groups differed significantly on several baseline smoking variables.

Blinding of participants and personnel (performance bias)
All outcomes
Unclear riskNot specified but due to nature of intervention, performance bias unlikely

Blinding of outcome assessment (detection bias)
All outcomes
High riskNo blinding reported, no biochemical validation used

Incomplete outcome data (attrition bias)
All outcomes
Low riskLoss to follow-up was 25% post-intervention, 21% for the 3-m follow-up survey, and 27% at 12 months. Survey non-response was higher among intervention participants then among controls (33% vs. 15%). All randomized participants included in ITT analysis.

 
Characteristics of excluded studies [ordered by study ID]

StudyReason for exclusion

Abelin 1989NRT double blind randomized trial for 112 young people. Reported follow-up was for three months only.

Abroms 2007Although strictly speaking the age range of the subjects in this study fall within those of interest to us, the mean age of subjects was 19.8 years and the population was a sub-set in higher education. We have excluded this study therefore but note the results OR:1.92 (95th % CI:0.35 to 10.52)

Adelman 2000RCT of a psycho-social intervention targeted at young people. Although measurements made at 6 months follow-up the control group were given the intervention three months after the intervention group, therefore only three month effectiveness data is available.

Adelman 2009NCT of nasal spray for 6 weeks plus counselling vs counselling alone. Unpleasant adverse effects, poor adherence, and consequent lack of efficacy did support the use of nicotine nasal spray as an adjunct to counselling. Outcome reported at 12 weeks therefore not added to review.

Ames 2007Median age of study subjects is 20 years with range 18-21 years. This age range is outside scope of this review.

An 2007Evaluates recruitment strategies, not smoking cessation

Audrain-McGovern 2011Although a cessation trial the intervention group could choose reduction rather than cessation as an outcome. Not added to data as not a pure cessation trial.

Audrey 2008Smoking prevention programme, not cessation

Bauman 2000The authors state that there were "no activities focused explicitly on cessation or reduction " in their intervention.

Bloor 1999Controlled trial using pupil advocates but only three month follow-up.

Bond 2004No discrete cessation component or results.

Bramley 2005Subjects of study outside age range of review

Braverman 1994Report not found but unlikely to be a trial

Brendryen 2008Trial of internet based support over 12 month period for over 18 year olds. Self reports of abstinence used with no verification. Main outcome repeated reports of abstinence at 1, 3, 6 and 12 months.

Burton 1994This is a report of the secondary cessation component/effects of the Project TNT intervention designed as a preventative programme. Follow-up is 4 months after start of trial. Summary paper published in 2009.

Cai 2000Intervention over 4 weeks and follow-up of cases for further three months. Excluded as not having six month follow-up but results from three months give no evidence of effectiveness:
1/12 (end of treatment OR=1.027 (0.57-1.84) and 4/12 from beginning of study = OR 0.971
(0.53-1.77)

Campbell 2008This trial was not designed as a pure cessation intervention.

Cavallo 2007Preliminary data giving end of treatment rates of cessation but no long term follow-up

Chen 2006Follow-up only 4 weeks so not eligible for this review

Colby 1998RCT of brief motivational interviewing in a hospital setting. Follow-up at three months so not eligible for this review.

Digiusto 1994This study, a "quasi-experiment" with pair matching for analysis, describes two interventions (same intervention but different time of delivery) and control. Control data on quitting collected at 6 months but data from one intervention arm collected at approximately 19 weeks after allocation.

Dino 1998West Virginia NoT with 3 and 4 month follow-up data from baseline

Egger 1983Community intervention, with cessation component and control population, aimed at adults in community over age of 18 years. Although subset of population this study was not aimed primarily at young people.

Ehrsam 1991Average age of participants in intervention group 21.9±6.8 years and control 24.1±6.9 years. Small size of overall study groups (56 cases in each arm) would mean it would be difficult to extract meaningful outcomes from sub-group analysis for age range of this review.

Elsasser 2002Conference paper: Trial of only 17 cases randomized to treatment or control therefore very underpowered. Outcome measured at 3/12.

Emmons 2003This study was long term follow-up of children who had had cancer. Current age of participants was 31±6.6 years.

Erol 2008Uncontrolled before and after study.

Escoffery 2004Phrogramme aimed at college students over 18 years of age. Average age of participants was 21 years.

Faessel 2009Clinical trial of safety and tolerability and pharmacokinetics of 14 days of high dose varenicline. Study design did not include cessation outcomes.

Fagan 2003This was an RCT designed to control tobacco use amongst young people and based in the workplace. Outcomes were reduction of use and intention to quit measures rather than actual cessation.

Figa-Talamanca 1989Educational RCT aimed at whole class groups and not specifically smokers.

Flay 1995Primarily a prevention programme and measured outcomes were in terms of knowledge and intention to quit. Cessation component not discrete.

Gray 2011A trial of sustained release bupropion combined with contingency management. The primary outcome was 7-day cotinine-verified point prevalence abstinence but follow-up was only for 12 weeks.

Hamilton 2005A school based cluster randomized controlled trial designed to test a harm minimisation approach. Only prevalence data available, no discrete results for smokers.

Hancock 2001Trial of community intervention aimed at teenagers that reported population prevalence of smoking rather than following up individual smokers.

Hanson 2003Trial of NRT(patches) for 13-19 year olds. Abstinence reported at 10 weeks post quit date.

Hanson 2006A harm reduction study rather than cessation.

Harris 2010This study was aimed at young adults. The mean age of participants was 19.4yrs in a range 18 to 22 years.

Haug 2009Study of SMS intervention for young adults. Mean age = 25 years.

Heikkinen 2009Finish study of smokers aged 15-16. Two intervention groups, information and support offered by dentist or school nurse. Only 3 month follow-up.

Hellmann 1988Although (quasi) experimental in design there was no formal randomization or attempt to case match and baseline characteristics have not been assessed or compared.

Helstrom 2004Potentailly interesting study with positive results but follow-up only 5 months in initial report.

Higgs 2000This primarily a prevention trial reporting secondary cessation effects.

Hollis 1994Not targeted at regular smokers and discrete quitting data not available.

Horn 2004Report of West Virginia trial with 3 month follow-up data only.

Hort 1995In prevention review. No discrete cessation programme.

Jason 1982This is essentially a trial of two whole class prevention strategies.

Josendal 1998Primarily a prevention study.

Kang 2005Excluded as follow-up is 4 weeks.

Kealey 2009Telephone counselling intervention (Motivational Interviewing and CBST) with matched pair design.

Kelleher 1999Smoking cessation was a component of an intervention to reduce cardiovascular risk. No discrete results measured.

Kentala 1999Intervention by dentists to discuss smoking during annual check up. Young people randomized to brief intervention or normal care. Prevalence data only collected. Individual smokers not followed up.

Killen 1988This is a cardiovascular health promotion trial with a smoking cessation component but without discrete results for individual smokers.

Kim 2004No discrete cessation component in report.

Krishkowy 2008Prevention study.

Lando 2007Study experienced some recruitment issues and it is not clear that all participants were active smokers.

Lotecka 1983Cognitive Behavioural intervention trialled in four schools. No discrete results available and follow-up three months.

McCambridge 2004Follow-up of smoking component was 3 months only.

McCuller 2006Project EX intervention that reports 3 month follow-up.

Mermelstein 2006Follow-up 3 months only.

Myers 2008Although a smoking cessation intervention, it is targeted at and outcomes recorded for other substances.

Niederhofer 2004Trial of bupropion versus placebo. Effectiveness measured at 90 days (three months).

Norman 2008No discrete quit data available. Confirmed with author.

O'Neill 2000Computer-based intervention using stage change model. The mean age of participants was 19.7 years range 18 years to 25 years. This falls outside our definition for this review.

Pallonen 1998This was a comparison trial between two interventions. There was no control group randomized to "placebo"/no intervention. The authors state "The inclusion of two different interventions (for smokers) rather than a treatment/control comparison is for process analysis since the sample size was inadequate for a clinical trial." The number of smokers in study was 135.

Pbert 2006Excluded as follow-up only 3 months.

Pbert 2008Not specifically targeted at smokers and no discrete results available at this time.

Perry 1980This is primarily a prevention study as the stated aim is to influence the incidence of smoking. The results are presented in such a form that overall prevalence is measured for a whole year group and discrete smokers cannot be identified.

Quinlan 2000Clinical trial using intervention matched to stage of change (TTM). Age range 18 years to 55 years. Mean age by group of participants was 20.41 yrs, 21.71 and 23.3 years and therefore this study falls outside the scope of this review.

Rabius 2004The age range of this study includes a cohort of 18 to 15 year olds. it is not possible to disaggregate 18 and 19 year olds from report of study but author contacted for primary data. If available this data will be incorporated in future versions of review.

Rice 2010Study based on Project TNT. Non random allocation instead compared cohorts in different years.

Roddy 2006Although this study meets all other inclusion criteria the outcome is measured at 13 weeks. This review uses Russell Standards, i.e. a minimum of a 6 month follow-up.

Rubinstein 200812 week follow-up only.

Schepis 2006Excluded as outcome is measured at 4 weeks.

Severson 1991Essentially a prevention study.

Simmons 2011Test of web-based intervention in American college students, participants older than 18.

Sims 2011Reports outcomes for young adults aged 18-24; average age not reported but over 20. Original study intended to recruit adolescents smokers but low recruitment, and results for 52 adolescents not reported.

Solomon 2009Outcomes long term prevalence of smoking.

Stein-Seroussi 2009Cluster randomised trial including biochemical verification of cessation. Outcome reported after 90 day follow-up.

Stephens 2001Good quality trial of Motivational Enhancement for young people but follow-up only 30 days at end of an intervention of 5 weeks duration. Author notes a high drop out rate.

Stoddard 2005Prevalance only measured, no discrete cessation data.

Sussman 1995This is a trial of Project TNT, an intervention based on cessation intervention clinics. Outcomes are self reported at 4 months after start of intervention.

Sussman 2007No discrete quitting data available. Authors contacted. Quitting rates, adjusted for mFTQ, given as 15% for programme group and 8% for control group.

Travis 2009Excluded as aimed at college students with participants median age 21±3 years and only 3 month follow-up.

Turner (NOT) 2006A version of NoT with web based component added. Only 3/12 follow-up.

Wang 2006Not a trial of intervention but a correlation analysis.

Werch 2008Trial of brief, image based multiple behaviour intervention for adolescents and college students. Aimed at range of substance abuse.Three month follow-up.

Whittaker 2011Although recruiting over 16 years of age, mean age of participants was 27 years +/- 8.7

Winkleby 2004Programme aims were to reduce smoking and although gives 6/12 follow-up discrete results not available for individual smokers as unit of analysis was school.

Wongwiwatthananukit 2009Trial of pharmacist-based cessation programme for youth offenders, one arm voluntary cessation one arm compulsory cessation. Excluded as non-randomised allocation as part of criminal justice process.

 
Characteristics of studies awaiting assessment [ordered by study ID]
Minary 2009

MethodsQuasi-experimental study in 8 vocational training centres

Participants1,814 students, at baseline 52% were smokers and 5.7% ex-smokers

InterventionsTABADO program, which included a general information session for all students and small-group sessions plus individual counselling and nicotine therapy, if needed, for volunteers in an enhanced program. The control group received no specific intervention other than the educational services usually available. .

OutcomesThe primary outcome was 30-day point prevalence abstinence at 12 months

NotesResults published after date of searches

 
Characteristics of ongoing studies [ordered by study ID]
Arora 2010

Trial name or titleProject ACTIVITY

MethodsRandomised controlled trial

ParticipantsParticipants recruited from 14 slum communities in Delhi, India

InterventionsMultiple strategies including community training for peer leaders and activists, community based interactive activities and outreach programmes such as films and street rallies, comic books and sticker cards, community based clinics and face-to-face counselling

OutcomesRates of tobacco use, past 6 months and 30 days smoking history, cessation rates

Starting datenot specified

Contact informationMs. Monika Arora, Director HRIDAY (Health Related Information Dissemination Amongst Youth). Address
for Correspondence: HRIDAY, C-1/52, 3rd Floor, Safdarjung Development Area, New Delhi-110016, India, monika@hriday-shan.org, monika.arora@phfi.org, Telephone No: 91-11-26850342;91-41031191, Fax No: 91-11-26850331.

NotesAdded 2013

Varenicline-NCT01312909

Trial name or titleSmoking Cessation in Healthy Adolescent Smokers

MethodsRandomised control trial

ParticipantsHealthy smokers aged 12-19

InterventionsVarenicline 1mg bd, 0.5 mg bd or placebo

OutcomesReduction or abstinence through to week 52

Starting dateTBC

Contact informationPfizer 1-800-718-1021

NotesAdded 2013

 
Comparison 1. Effect sizes for all studies with extractable data

Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size

 1 Subgroups by abstinence definition27Risk Ratio (M-H, Fixed, 95% CI)Totals not selected

    1.1 Sustained or prolonged abstinence
4Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

    1.2 30 day point prevalence abstinence
8Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

    1.3 7 day point prevalence abstinence
12Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

    1.4 Other abstinence measure
9Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

 2 New studies in 20134Risk Ratio (M-H, Fixed, 95% CI)Totals not selected

 
Comparison 2. TTM vs standard care or dietary advice

Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size

 1 Cessation at 1 year31662Risk Ratio (M-H, Fixed, 95% CI)1.56 [1.21, 2.01]

 2 Cessation at 2 years21537Risk Difference (M-H, Fixed, 95% CI)0.03 [-6.17, 0.06]

 
Comparison 3. Motivational enhancement vs brief interventions

Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size

 1 Cessation at 6 months or longer122667Risk Ratio (M-H, Fixed, 95% CI)1.60 [1.28, 2.01]

 2 Complex interventions including Motivational Interviewing61583Risk Ratio (M-H, Fixed, 95% CI)1.88 [1.30, 2.72]

 
Comparison 4. Interventions including Cognitive Behavioural Techniques

Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size

 1 Cessation at 6 months or longer13Risk Ratio (M-H, Fixed, 95% CI)Totals not selected

 
Comparison 5. Complex interventions using M I, Social cognitive theory, CBT or/and TTM

Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size

 1 Biochemically verified 6 month continuous abstinence2456Risk Ratio (M-H, Fixed, 95% CI)1.18 [0.80, 1.72]

 2 6 month continuous cessation2836Risk Ratio (M-H, Fixed, 95% CI)1.72 [1.03, 2.86]

 3 Cessation at 6 months, ≧ 7days PPA1402Risk Ratio (M-H, Fixed, 95% CI)1.10 [0.74, 1.62]

 
Comparison 6. NoT (Not on Tobacco)

Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size

 1 Cessation at 6 months or longer61420Risk Ratio (M-H, Fixed, 95% CI)1.31 [1.01, 1.71]

 2 NoT+Fit vs Control1143Risk Ratio (M-H, Fixed, 95% CI)1.97 [1.02, 3.79]

 3 NoT+Fit vs NOT1170Risk Ratio (M-H, Fixed, 95% CI)1.48 [0.88, 2.48]

 
Comparison 7. ICT-based interventions

Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size

 1 30 day PPA at 6 months1139Risk Ratio (M-H, Fixed, 95% CI)0.44 [0.14, 1.36]

 2 7 day PPA at 12 months2Risk Ratio (M-H, Fixed, 95% CI)Totals not selected

 3 30 day abstinence at 12m1448Risk Ratio (M-H, Fixed, 95% CI)1.80 [1.19, 2.71]

 
Comparison 8. Pharmacological interventions

Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size

 1 Point prevalence abstinence at six months3Risk Ratio (M-H, Fixed, 95% CI)Totals not selected

    1.1 Nicotine patch + bupropion versus nicotine patch + placebo
1Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

    1.2 Nicotine patch versus placebo
1Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

    1.3 Nicotine gum versus placebo
1Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

    1.4 Bupropion vs placebo
1Risk Ratio (M-H, Fixed, 95% CI)0.0 [0.0, 0.0]

 
Comparison 9. Russell Standards

Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size

 1 Biochemically verified 6 month continuous abstinence2456Risk Ratio (M-H, Fixed, 95% CI)1.18 [0.80, 1.72]

 
Summary of findings for the main comparison. Transtheoretical Model of Change (TTM) for smoking cessation in young people

Transtheoretical Model of Change (TTM) compared to standard care or dietary advice for smoking cessation in young people

Patient or population: young people
Intervention: TTM
Comparison: standard care or dietary advice

OutcomesIllustrative comparative risks* (95% CI)Relative effect
(95% CI)
No of Participants
(studies)
Quality of the evidence
(GRADE)
Comments

Assumed riskCorresponding risk

Standard care or dietary adviceTTM

Cessation
Self-report
Follow-up: 12 months
103 per 10001160 per 1000
(124 to 207)
RR 1.56
(1.21 to 2.01)
1662
(3 studies)
⊕⊕⊝⊝
low2,3

*The basis for the assumed risk (e.g. the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).
CI: Confidence interval; RR: Risk ratio;

GRADE Working Group grades of evidence
High quality: Further research is very unlikely to change our confidence in the estimate of effect.
Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.
Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.
Very low quality: We are very uncertain about the estimate.

 1 Assumed risk is average across control groups
2 All three studies judged to be at unclear or high risk of bias in at least one domain
3 Small number of total events (>300)
 
Summary of findings 2. Interventions including motivational enhancement for smoking cessation in young people

Interventions including motivational enhancement compared to brief interventions for smoking cessation in young people

Patient or population: young people
Intervention: Interventions including motivational enhancement
Comparison: brief interventions

OutcomesIllustrative comparative risks* (95% CI)Relative effect
(95% CI)
No of Participants
(studies)
Quality of the evidence
(GRADE)
Comments

Assumed riskCorresponding risk

Brief interventionsInterventions including motivational enhancement

Cessation
Majority self report (some biochemical validation)
Follow-up: 6+ months
87 per 10001138 per 1000
(111 to 174)
RR 1.6
(1.28 to 2.01)
2667
(12 studies)
⊕⊕⊕⊝
moderate2

*The basis for the assumed risk (e.g. the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).
CI: Confidence interval; RR: Risk ratio;

GRADE Working Group grades of evidence
High quality: Further research is very unlikely to change our confidence in the estimate of effect.
Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.
Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.
Very low quality: We are very uncertain about the estimate.

 1 Assumed risk based on average across control groups in each study
2 Large majority of included studies judged to be at high or unclear risk of bias in at least one domain
 
Summary of findings 3. Not on Tobacco (NoT) programmes for smoking cessation in young people

Not on Tobacco (NoT) programmes for smoking cessation in young people

Patient or population: young people
Intervention: Not on Tobacco programmes

Comparison: brief interventions

OutcomesIllustrative comparative risks* (95% CI)Relative effect
(95% CI)
No of Participants
(studies)
Quality of the evidence
(GRADE)
Comments

Assumed riskCorresponding risk

ControlNoT

Cessation
Follow-up: 6+ months
104 per 1000137 per 1000
(105 to 178)
RR 1.31
(1.01 to 1.71)
1420
(6 studies)
⊕⊕⊝⊝
low1,2

*The basis for the assumed risk (e.g. the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).
CI: Confidence interval; RR: Risk ratio;

GRADE Working Group grades of evidence
High quality: Further research is very unlikely to change our confidence in the estimate of effect.
Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.
Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.
Very low quality: We are very uncertain about the estimate.

 1 Majority of studies at high risk of bias in at least one domain
2 Small number of total events (<300)