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Initial report of the cancer Patient-Reported Outcomes Measurement Information System (PROMIS) sexual function committee
Review of sexual function measures and domains used in oncology
Article first published online: 4 FEB 2009
Copyright © 2009 American Cancer Society
Volume 115, Issue 6, pages 1142–1153, 15 March 2009
How to Cite
Jeffery, D. D., Tzeng, J. P., Keefe, F. J., Porter, L. S., Hahn, E. A., Flynn, K. E., Reeve, B. B. and Weinfurt, K. P. (2009), Initial report of the cancer Patient-Reported Outcomes Measurement Information System (PROMIS) sexual function committee. Cancer, 115: 1142–1153. doi: 10.1002/cncr.24134
- Issue published online: 3 MAR 2009
- Article first published online: 4 FEB 2009
- Manuscript Accepted: 15 SEP 2008
- Manuscript Revised: 11 AUG 2008
- Manuscript Received: 13 MAY 2008
- National Institutes of Health. Grant Number: U-5-U01-AR052186
- quality of life;
- sexual function
For this report, the authors described the initial activities of the Cancer Patient-Reported Outcomes Measurement Information System (PROMIS)-Sexual Function domain group, which is part of the National Institutes of Health Roadmap Initiative to develop brief questionnaires or individually tailored assessments of quality-of-life domains. Presented are a literature review of sexual function measures used in cancer populations and descriptions of the domains found in those measures. By using a consensus-driven approach, an electronic bibliographic search was conducted for articles that were published from 1991 to 2007, and 486 articles were identified for in-depth review. In total, 257 articles reported the administration of a psychometrically evaluated sexual function measure to individuals who were diagnosed with cancer. Apart from the University of California-Los Angeles Prostate Cancer Index, the International Index of Erectile Function, and the Female Sexual Function Index, the 31 identified measures have not been tested widely in cancer populations. Most measures were multidimensional and included domains related to the sexual response cycle and to general sexual satisfaction. The current review supports the need for a flexible, psychometrically robust measure of sexual function for use in oncology settings and strongly justifies the development of the PROMIS-Sexual Function instrument. When the PROMIS-Sexual Function instrument is available publicly, cancer clinicians and researchers will have another measure with which to assess patient-reported sexual function outcomes in addition to the few legacy measures that were identified through this review. Cancer 2009. © 2009 American Cancer Society.
In 1987, the American Cancer Society published a review article on sexual function and cancer to encourage clinicians to address the sexual concerns of cancer survivors.1 Since then, the number of individuals alive with a history of cancer in the US population has almost doubled from an estimated 5.9 million to an estimated 11.1 million.2 Thus, although the number of cancer survivors who consider sexual function to be an essential component of quality of life is increasing, the assessment and treatment of sexual concerns or sexual dysfunction has yet to be practiced routinely in oncology settings.3 The prevalence of sexual dysfunction for all cancer survivors is unknown, but the rate of erectile dysfunction may be as high as 100% among prostate cancer survivors after radical prostectomy,4 and the rate of problems with sexual desire or orgasms disorders may be as high as 75% among ovarian cancer survivors.5 The detection and treatment of sexual problems and an understanding of how various cancer treatments affect sexual function are important issues, because sexual dysfunction may disrupt relationship intimacy, contribute to emotional distress, reinforce negative body image, or serve as a constant reminder of a patient's cancer history. Identifying the presence and severity of sexual concerns should be considered part of cancer treatment and follow-up care,6, 7 because such concerns are likely to be long-standing or to worsen over time.8 In addition, the assessment of sexual function in clinical settings may help inform treatment choice, most notably for prostate, gynecologic, breast, and colorectal cancer treatments. Such assessment may provide data that lead to modifications of surgical approaches9, 10; the type and dosage of chemotherapy11, 12; the timing, location, type and amount of radiation13; the timing and maintenance schedule of hormone therapy14; and post-treatment symptom management.15, 16
Unfortunately, efforts to characterize the epidemiology and treatment of sexual problems in cancer have been hampered by a lack of consensus regarding valid outcome measures that can be used in a variety of contexts.4, 17-19 This shortcoming is not unique to cancer, as documented in the review by Arrington et al20 of sexual function instruments that are used with general and medically ill populations. To facilitate communication between cancer survivors and their physicians and to design informative clinical research, the field requires a measure that can be used across the continuum of care for different cancer sites and stages of disease, regardless of sex, sexual orientation, partner status, age, literacy level, or cultural background. Ideally, such a measure would be sensitive to differential treatment effects when applicable; would be able to detect clinically meaningful changes in sexual function; would be sufficiently flexible to provide tailored assessments based on personal, illness, and treatment characteristics; and would generate information that is useful for implementing and evaluating clinical interventions. A measure of sexual function developed specifically for cancer populations, likewise, may serve as a diagnostic tool in cancer and other chronic diseases and may assist in the systematic documentation of this quality-of-life domain.
In response to this assessment need, the National Cancer Institute is funding a supplement to the National Institutes of Health (NIH) Roadmap Initiative for the Patient-Reported Outcomes Measurement Information System (PROMIS)21, 22 and collaborating with Duke University Medical Center and NorthShore University HealthSystem Research Institute to develop a computerized measure of sexual function that addresses the concerns detailed above. Specifically, item banks will be created to allow researchers the flexibility to assess sexual functioning with either brief, fixed-length questionnaires or individually tailored assessments (ie, computerized-adaptive testing [CAT]). Item banks are groupings of questions with measurement properties that are calibrated carefully so that they can provide an operational definition of a concept (eg, satisfaction with sex life) and accurately assess the entire continuum (eg, severity or frequency) of that concept.23 We are using the developmental process of the PROMIS item banks,21, 24 which integrates the methods from qualitative research, psychometrics, health survey methods, and informatics, to create efficient, precise, and valid measures that focus on sexual function. The key to this process is the continual input from cancer patients, clinicians, and survey methodologists to create the PROMIS-Sexual Function (PROMIS-SF) item banks.
The purpose of this review is to report on the initial activities of the NIH-funded Cancer PROMIS Supplement Sexual Function (CaPS-SF) domain group. Specifically, we present selected findings from our CaPS-SF literature review of sexual function measures that are used in cancer populations and describe how we identified the major sexual function domains used in those measures. Our secondary purpose is to provide oncology clinicians a compendium of psychometrically tested, patient-reported measures of sexual function along with corresponding cancer research citations. Although our major intent is to inform the oncology community about the development of PROMIS-SF, we use the compendium to guide our recommendations to oncology clinicians and researchers in their current efforts to assess the sexual function of their patients.
MATERIALS AND METHODS
By using a modified Delphi, consensus-driven approach developed by the PROMIS Steering Committee,23 we conducted an electronic bibliographic search using OVID Medline to identify measures of sexual function that are used in cancer populations. We used the search terms ‘cancer’ or ‘neoplasms’ in combination with 2 other sets of search terms under the rubrics of ‘measurement’ and ‘sexual function.’ Additional electronic searches were conducted using the PsychInfo, PubMed, HAPI, Embase, CINAHL, and SCOPUS (1992-2007) databases. Approximately 1200 citations were generated. The following criteria were used to select a final subset of 486 articles for in-depth review: the article was research-based, was published in English between 1991 and 2007, described a sample of participants diagnosed with cancer, and described the administration of a self-report measure of sexual function.
The in-depth review ascertained the name(s) of the sexual function measure(s), the domains included in the measure, the original instrument citation(s), the numbers and types of items, the types of responses, the sample size, and the characteristics of the cancer population. When possible, the original psychometric report for each measure was reviewed to obtain information about dimensionality, domains, the type of psychometric analysis, and the overall reliability and validity. We coded the type(s) of reliability as internal consistency (Cronbach α coefficient, Kuder-Richardson Formula 20), test-retest (Pearson correlation coefficient, interclass correlation coefficients), split-half (Spearman-Brown prophecy formula, Guttman split-half reliability coefficient, Rulon formula), and inter-rater agreement (κ statistic or intraclass correlation coefficients). Validity, for purposes of this review, was classified as content, construct (convergent validity or discriminant validity), and criterion (concurrent validity or predictive validity).25 In a few instances, we contacted the developer(s) of the measure to obtain psychometric information and to inquire about the measure's use in oncology.
From a review of 486 cancer-related articles, a total of 257 articles were identified that described the use of at least 1 dedicated, self-report, sexual function measure with documented levels of reliability and validity. Approximately 76% of these articles focused on prostate cancer, 9% focused on breast cancer, 7% focused on gynecologic cancers, and 2% each focused on bladder, rectal, testicular, hematologic, and head and neck cancers. Table 1 lists the 31 unique self-report measures that we identified. Although it was not a dedicated sexual function measure, we included the University of California-Los Angeles (UCLA) Prostate Cancer Index (PCI),26 because it was used in half of the reviewed studies that focused on prostate cancer; in that index, items on sexual function and sexual bother are included with items about urinary and bowel function and bother.
|Instrument Name [References]*||Domains and Internal Consistency||Reliability and Validity||Cancer Site and Reference(s)*|
|Arizona Sexual Experience Scale (ASEX) [McGahuey et al, 2000]||Sex drive, arousal, lubrication/erection, ability to reach orgasm, satisfaction from orgasm||Overall, α=.91; concurrent, construct||Cancer sites in women: Mathias et al, 2005; breast: Mathias et al, 2006|
|Brief Index of Sexual Functioning for Women (BISF-W) [Taylor et al, 1994; Mazer et al, 2000]||Sexual interest/desire, sexual activity, sexual satisfaction||Internal consistency of subscales, α=.39-.74; overall, α=.83; test-retest, r=0.68-0.78; concurrent, construct||Breast or gynecologic/stage I-IIb: Scott et al, 2004; gynecologic: Du et al, 2005; prostate (spouses): Soloway et al, 2005|
|Brief Sexual Function Questionnaire for Men (BSFQ) [Reynolds et al, 1988]||Sexual activity/performance, interest, satisfaction, physiologic competence||Guttman total test-retest reliability, r=0.94; concurrent, construct||Prostate: Soloway et al, 2005|
|Brief Sexual Function Inventory (BSFI) [O'Leary et al, 1995]||Interest, function, ejaculation, problems/satisfaction||Internal consistency of domains, α=.62-.92; test-retest. r=0.68-0.70; concurrent, construct||Prostate: Bradley et al, 2004; Deliveliotis et al, 2004; Rajagopal et al, 2003; Valicenti et al, 2001, 2002; Chen et al, 2001; Krupski et al, 2000; Hong et al, 1999|
|Changes in Sexual Functioning Questionnaire (CSFQ) [Clayton 199734; Clayton et al, 1997; Keller et al, 2006]||Desire/frequency, desire/interest, arousal/excitement, orgasm/ completion, pleasure||Internal consistency of domains, α=.64-.80; test-retest, r=0.45-1.00; construct||All cancer sites in women: Barton et al, 2007; gynecologic: Lagana et al, 2005; Caldwell et al, 2003|
|Derogatis Interview for Sexual Functioning-Self Report (DISF-SR) [Derogatis 199734]||Cognition/fantasy, arousal, sexual behavior, orgasm, drive||Internal consistency of domains, α=.74-.80||Cervical cancer: Schroder 200556|
|Derogatis Sexual Functioning Inventory (DSFI) [Derogatis, 1979]||Information, experience, drive, attitudes, psychological distress, gender role, fantasy, body image, sexual satisfaction, frequency of activity||Internal consistency of domains, α=.56-.97; test-retest, r=0.61-0.96; construct||All sites: Ananth et al, 2003; breast: Young-McCaughan 199612; cervix: Grumann et al, 2001; Schroder 200558; head and neck: Monga et al, 1997; hematologic: Marks et al, 1996|
|Erectile Dysfunction-Effect on Quality of Life (ED-EQoL) [MacDonagh et al, 2004]||Erectile dysfunction||Internal consistency, α=.94; construct (discriminant: Ferguson δ=0.86)||Prostate: Meyer et al, 2003|
|Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS) [Althof et al, 1999]||Erectile dysfunction||Internal consistency: patient, α=.90; partner, α=.76; test-retest: patient, r=0.98; partner, r=0.83; content||Prostate: Ramsawh et al, 2005; Montorsi et al, 2004|
|Female Sexual Function Index (FSFI) [Rosen 200030; Wiegel et al, 2005]||Desire, arousal, lubrication, orgasm, satisfaction, pain||Internal consistency, α>.90; test-retest, r=0.79-0.86; construct||Bladder: Bhatt 200654; breast: Schover 200660; Speer 200561; cervix: Frumovitz 2005,55 Schroder 200556; gynecologic: Carter 200557; rectal: Hendren 2005,62 Jayne 200563; vulvar: Likes 200758, 59|
|Golombok Rust Inventory of Sexual Satisfaction (GRISS) [Rust et al, 1985, 1986; ter Kuile et al, 1999; van Lankveld et al, 1999, 2003]||Erectile dysfunction, premature ejaculation, anorgasmia, vaginismus, noncommunication, infrequency; both men and women: avoidance, nonsensuality, dissatisfaction||Internal consistency of subscales, α=.72-.98; test-retest of subscale, r=0.72-0.90; predictive, construct||Breast: Onen Sertoz et al, 2004; testicular: Sheppard et al, 2001|
|International Continence Society questionnaire (ICS) (men and sex subscales) [Donovan et al, 2000]||Erectile function||Internal consistency of subscales, α=.69-.91; test-retest of symptom score, r=0.78; problem score, r=0.83; criterion, construct||Prostate: Henderson et al, 2006; Rozet et al, 2005; Selli et al, 2004; Gacci et al, 2003; Hara et al, 2003|
|Index of Female Sexual Function (IFSF-modified) [Kaplan et al, 1999; Zippe et al, 2004]||Free of pain during intercourse, degree of vaginal lubrication, overall sexual desire and interest, ability to achieve orgasm, overall sexual satisfaction||Internal consistency, α=.80-.90; test retest of subscales, r=0.71-0.76; total scale, r=0.70; construct||Bladder: Zippe et al, 2004|
|International Index of Erectile Function, Sexual Health Inventory for Men (IIEF-15, SHIM, IIEF-5) [Rosen 1997,28 1999,29 200247; Rhoden et al, 2002; Cappelleri et al, 2005]||Erectile function, orgasm, desire, intercourse satisfaction, overall satisfaction; IIEF-5: erectile function, intercourse satisfaction||Internal consistency of domains, α=.73-.99; test-restest of domains, r=0.64-0.84; construct||Bladder: Davila et al, 2007; Wang et al, 2007; Columbo et al, 2004; prostate: Cesaretti 200713; Chang et al, 2007; Davison et al, 2004, 2007; Incrocci 2006,15 200752; Kava et al, 2007; Kohler et al, 2007; Lee et al, 2007; Lu et al, 2007; Madeb et al, 2007; Mattei, 2007; Matthew et al, 2007; Papadoukakis et al, 2007; Wille et al, 2007; Zagar et al, 2007; Bannowsky et al, 2005, 2006; Chaplin et al, 2006; Col et al, 2006; Kim et al, 2006; Long et al, 2006; Latini et al, 2006a,b; Ponholzer et al, 2005, 2006; Salonia et al, 2006; Titta et al, 2006; Wilke et al, 2006; Zucchi et al, 2006; Bellina et al, 2005; Canada et al, 2005; De Lorenzo et al, 2005; Dinelli et al, 2005; Karakiewicz et al, 2005; Mabjeesh et al, 2005; Menon et al, 2003, 2005; Matzkin et al, 2001, 2005; Merrick et al, 2001, 2005; Mulhall et al, 2005; Ohebshalom et al, 2005; Pompeu et al, 2005; Porpiglia et al, 2005; Rozet et al, 2005; Shindel et al, 2005; Trinchieri et al, 2005; Yatim, 2005; Alduais et al, 2004; Colombo et al, 2004; Fujioka et al, 2004; Montorsi et al, 2004; Ogura et al, 2004; Raina et al, 2004; Saidi et al, 2004; Anastasiadis et al, 2003; Gacci et al, 2003; Hara et al, 2003; Incrocci et al, 2001, 2003; Lee et al, 2003; Penson et al, 2003; Raina et al, 2003; Noldus et al, 2002; Schover et al, 2002a,b; Saito et al, 2001; Blander et al, 2000; Kedia et al, 1999; testicular: Wiechno et al, 2007; Lackner et al, 2005; rectal: He & Pu, 2005; Hendren 200562; Jayne 200563|
|Medical Outcomes Study (MOS) Sexual Functioning Scale (MOS-SFS) [Sherbourne, 1992; McHorney et al, 1994; Hays et al,1993]||Sexual activity, difficulty becoming aroused, difficulty relaxing/enjoying sex, difficulty achieving orgasm||Internal consistency, α=.90 (men), r=0.92 (women); construct||Breast: Burwell et al, 2006; Broeckel et al, 2002; head and neck: Siston et al, 1997|
|University of California-Los Angeles (UCLA) Prostate Cancer Index-Sexual Function/Sexual Bother (PCI-SF/SB) [Lubeck et al, 1997; Litwin 199826; Litwin et al, 2002; Karakiewicz et al, 2003; Krongrad, et al, 1998]; UCLA Prostate Cancer Index + [Dutch] Sexual Activities module [Incrocci et al, 2001; Korfage et al, 2003]; UCLA Expanded Prostate Index Composite (EPIC) [Wei 200027]; Japanese-adapted EPIC [Takegami et al, 2005; Kakehi et al, 2007; Namiki et al, 2007a]||Sexual function; sexual bother||Internal consistency of subscales, α>.78; cross-cultural validity, construct||Prostate: Anger et al, 2007; Arredondo 200749; Ash et al, 2007; Campbell et al, 2004, 2007; Dearnaley et al, 2007; Frank et al, 2007; Kakehi et al, 2007; Kato et al, 2007; Kubler et al, 2007; Litwin et al, 1999, 2001, 2007; Namiki et al, 2006, 2007b,c; Penedo et al, 2007; Stevens et al, 2007; Van der Wielen et al, 2007; Ball et al, 2006; Dalkin et al, 2006; Ishihara et al, 2006; Joseph et al, 2006; Miller 200616; Montgomery et al, 2006; Newton et al, 2006; Pinkawa et al, 2006a,b; Sanderson et al, 2006; Tseng et al, 2006; Wagner et al, 2006; Dahn et al, 2004, 2005; Descazeaud et al, 2004, 2005; Jayadevappa et al, 2005; Korfage et al, 2005; Krupski et al, 2005; Link et al, 2005; Penson et al, 2001, 2003, 2005; Soderdahl et al, 2005; Steginga et al, 2005; Wiygul et al, 2005; Yang et al, 2005; Hoffman et al, 2004; Hollenbeck 200414; Hu et al, 2004; Jenkins et al, 2004; Lepore et al, 2004; Merrick et al, 2004; Namiki et al, 2004a,b; Schover et al, 2004; Su et al, 2004; Cooperberg et al, 2003; Downs et al, 2003; Hollenbeck et al, 2002. 2003; Korfage et al, 2003; Krahn et al, 2003; Oefelein, 2003; Bacon et al, 2002; Katz et al, 2002; Smith et al, 2000, 2002; Valicenti et al, 2002; Wei et al, 2002; Chen et al, 2001; Davis et al, 2001; Fulmer et al, 2001; Kupelian et al, 2001; Lubeck et al, 2001a,b; Madalinska et al, 2001a,b; Pietrow et al, 2001; Schapira et al, 2001; Brandeis et al, 2000; Gralnek et al, 2000; Potosky 200048; Sanchez-Ortiz et al, 2000; Perrotte et al, 1999; Krongrad et al, 1998; Litwin 199826; Yarbro et al, 1998|
|Psychological Impact of Erectile Dysfunction (PIED) [Latini et al, 2002]||Sexual experience; emotional life||Internal consistency of subscales, α=.72-.91; test-retest of subscales, r=0.66-0.76; construct||Prostate: Penson et al, 2003|
|Sapporo Medical University Sexual Function Questionnaire (SMUSFQ) [Kato et al, 1999]||Sexual desire, erectile function, satisfaction after sex, sexual activity, overall satisfaction||Reliability not reported; construct||Prostate: Yoshimura et al, 2003, 2004; Miyao et al, 2001; Arai et al, 1999; Shibuya et al, 1997|
|Radiation Therapy Oncology Group Sexual Adjustment Questionnaire: Modified Sexual Adjustment Questionnaire (RTOG SAQ-H) [Waterhouse et al, 1986; Bruner et al, 1998]||Activity, arousal, libido, orgasm, satisfaction, relationships, techniques, sexual dysfunction||Test-retest (women), r=0.67; construct||Prostate: Feigenberg et al, 2005; Bruner et al, 1998, 2004; gynecologic: Ratliff et al, 1996|
|Sexual Activity Questionnaire (SAQ) [Thirlaway et al, 1996]||Frequency of sexual activity, sexual interest/desire, arousal/vaginal dryness, sexually related pain||Internal consistency, α=.56-.88; test-retest, κ=0.50-1.0||Breast: Ganz, et al, 2002, 2003; Fobair et al, 2001; ovarian: Carmack Taylor 20045; gynecologic: Wenzel et al, 2002|
|Sexual Arousability Inventory (SAI) [Hoon et al, 1976]||Sexual arousability||Internal consistency, α=.91-.92; split half, r=0.92; content, construct||Breast: Wellisch et al, 1991, 1992, 1996|
|Sexual Adjustment Questionnaire (SAQ-modified) [O'Farrell et al, 1997]||Overall satisfaction, frequency of intercourse, discrepancy between desire and actual frequency, communication, ease of refusal, satisfaction with specific aspects, satisfaction with privacy and context, sexual dysfunction||Reliability not reported; content, construct||Prostate: Soloway et al, 2005|
|Sexual Beliefs and Information Questionnaire (SBIQ) [Adams et al, 1996]||Time/patience, stress/pressure, aging, sexual satisfaction, other/basic knowledge||Internal consistency: Total, α=.81; factors, α=.42-.93; test-retest, r=0.82; content||Gynecologic: Brotto et al, 2007|
|Sexual Function After Treatment for Gynecologic Cancer (SFAGIS) [Bransfield et al, 1984]||Fears about sexual activity, partner fears about sexual activity, initiation of activity, vaginal condition, vaginal lubrication, health provider intervention, desire for sexual information, changes in sexual activity||Split half, r=0.80; Kuder-Richardson 20 internal consistency, r=0.76; content||Gynecologic: Bruner et al, 1999|
|Sexual Function Inventory Questionnaire (SFIQ) [Klotz et al, 2000]||Not reported||Reliability and validity not reported||Prostate: Klotz et al, 2000|
|Sexual Function Questionnaire (SFQ) [Syrjala et al, 2000]||Sexual activity, specific problems, interest, desire, arousal, orgasm, satisfaction, masturbation, relationship||Internal consistency of domains, α>.80; overall, α=.94; criterion, construct||All cancers: Syrjala et al, 2000; hematologic: Syrjala et al, 2005|
|Sexual History Form (SHF) [Schover & Jensen, 1988]||Sexual behavior, frequency, satisfaction||Reliability on 12 of 28 original items: Internal consistency, α=.65 (men); test-retest, r=0.92 (women), r=0.98 (men)||Bladder: Hart et al, 1999; breast: Greendale et al, 2001; Mortimer et al, 1999; Makar et al, 1997; Schover et al, 1995; prostate: Perez et al, 2002|
|Sexual Self-Efficacy Scales (SSES)-Erectile Functioning (SSES-EF); SSES-Female Functioning (SSES-FF) [Fichten et al, 1998; Bailes et al, 1998]||SSES-EF: Unidimensional; SSES-FF: Interpersonal orgasm, individual interest/desire sensuality, individual arousal, affection, communication, body acceptance, refusal||SSES-EF: Internal consistency, α=.86-.92; test-retest, r=0.97-0.98; concurrent, construct; SSES-FF: Internal consistency, α=.93 (total), α=.70-.87 (subscales); test-retest, r=0.83 (total); r=0.50-0.93 (subscales); concurrent||Prostate: Latini et al, 2006; Penson et al, 2003|
|Sexual Self-Schema Scale (SSSS) [Andersen & Cyranowski, 1994]||Passionate-romantic, open, embarrassed-conservative||Intercorrelations, r=0.65-0.80; construct||Ovarian: Champion et al, 2007; Gershenson et al, 2007; prostate: Schover et al, 2002a,b, 2004; Jenkins et al, 2004; gynecologic: Andersen et al, 1997|
|Sexual function-Vaginal changes Questionnaire (SVQ) [Jensen 200432]||Sexual interest, lubrication, orgasm, dyspareunia, vaginal dimensions, intimacy, sexual problems of partner, sexual activity, sexual satisfaction, body image, sexual and vaginal problems||Internal consistency for subscales, α=.76-.83; median κ (patient/observer)=0.80; construct||Cervix: Jensen et al, 2003; Jensen 200432|
|Watts Sexual Function Questionnaire (WSFQ) [Watts, 1982]||Not reported||Internal consistency, α=.80; test-retest, r=0.83||Breast: Rowland et al, 2000; prostate: Basaria et al, 2002|
Only 3 measures with well documented reliability and validity were used in ≥10 of the reviewed articles: the UCLA PCI and its longer version, the Expanded Prostate Index Composite (EPIC)27; the International Index of Erectile Function (IIEF)28 and its shorter version, the IIEF-529; and the Female Sexual Function Index (FSFI).30 Approximately 34% of the 257 reviewed articles (n=87 articles) reported using the UCLA PCI or the EPIC, 30.7% (n=79 articles) reported using the IIEF, and 3.9% (n=10 articles) reported using the FSFI.
Only 3 of the identified measures appear to have been developed specifically for cancer populations, namely, the Sexual Function After Treatment for Gynecologic Cancer,31 the UCLA PCI,26 and the Sexual Function-Vaginal Changes Questionnaire.32 Almost all of the identified measures are sex-specific or have separate forms for men and women (eg, Derogatis Sexual Functioning Inventory,33 Changes in Sexual Functioning Questionnaire34) to permit matched comparisons.
In addition to the sexual function scales, several of the reviewed articles reported using functional status or quality-of-life measures that included 1 or more items related to sexual function. For example, the Functional Assessment of Cancer Therapy-Breast Scale35 assesses sexual function in its subscale about additional concerns, the Cancer Rehabilitation and Evaluation System Short Form contains a sexual function subscale,36 and the Psychosocial Adjustment to Illness Scale includes a subscale of sexual dysfunction and quality of dyadic relationship.37-39 Likewise, several of the site-specific measures of the European Organization for Research and Treatment of Cancer (EORTC) quality-of-life questionnaires (EORTC QLQ) contain function or symptom subscales to assess sexual function or dysfunction, such as the EORTC QLQ Colorectal-38, the EORTC QLQ Breast-23, the EORTC QLQ Ovarian-28, and the EORTC QLQ Head & Neck-35.40 In addition, Gotay and her colleagues,41 after conducting qualitative research with cancer survivors, added sexuality/intimacy items to the EORTC QLQ Cancer 30.
Dimensionality and Domains
Only a few measures were constructed purposively to be unidimensional, and most measures were multidimensional. Exploratory factor analysis or principal component analysis were the most common statistical methods used to identify or verify subdomains. No psychometric reports indicated the use of confirmatory factor analysis or item-response theory.
Almost all measures included domains related to stages of the sexual response cycle as defined by Masters and Johnson,42 including excitement/arousal, plateau/continued arousal and orgasm, although the specific content varied considerably between measures. The most common domains and the number of measures identifying these domains were:
Sexual arousal (lubrication, erectile [dys]function; 19 measures),
Sexual (dis)satisfaction (16 measures),
Sexual desire (interest, drive, avoidance, receptivity, nonsensuality; 15 measures),
Sexual pleasure (orgasm; 12 measures),
Frequency of sexual activity (12 measures), and
Problems affecting sexual function (anorgasmia, pain, vaginismus; 5 measures).
Less common domains (or constructs) related to cognitive aspects include sexual thoughts or fantasies, sexual self-esteem, sexual self-image, sexual self-reflection, psychosexual stimulation, emotional goals, and broader cognitive dimensions, such as sexual attitudes and beliefs, motivation, values, and expectations. The most infrequent domains were sexual role, partner function or perceptions, nonsexual interactions or communication, relationship satisfaction, and health-specific sexual dysfunction. Our preliminary conceptual model, based on the sorting of the measures' reported domains, contains 5 domains: sexual response, intrapersonal, interpersonal, frequency, and overall satisfaction.
Our literature review highlights the wide array of sexual function measures administered to cancer populations. Although we focused exclusively on the cancer literature, our findings approximate those of other reviews that examined the domains and psychometric properties of sexual function instruments that are used with general and medically ill populations. The first review by Arrington et al20 identified 45 sexual function-specific measures and 12 global measures; and those authors concluded that, although there is no consensus on sexual function domains, the most common domains were excitement/arousal, interest/desire, satisfaction/quality, and performance. The second review by Corona et al17 identified 30 patient self-report measures of sexual function that were published in their entirety between 1969 and 2005, including 22 measures for men and/or men or women and 8 measures for women only. Our secondary review of these 30 measures identified 83 unique domains, the most common relating to psychological constructs (eg, emotional responses to sexual problems, sexual concerns), sexual desire/interest, sexual partner or relationship, and overall sexual satisfaction or pleasure. These domains are consistent with our preliminary conceptual model, which is expected to undergo revision after further qualitative and quantitative testing.
For measures of sexual function in men, there appears to be complete accord for including erectile function as a domain. For measures of sexual function in women, sexual interest or desire and the ability to reach orgasm are the most common domains. In contrast, there appears to be no consensus among measures for both men and women with respect to domains related to nongenital activity, affection behaviors, or sexual intimacy, and, rarely, partner sexual function, sexual attractiveness or body-image, or sexually related cognitive or emotional dimensions. Others recommend classifying these latter domains as secondary or mediating dimensions.19, 43-45
Most of the identified measures were sex-specific, consistent with other reviews of general sex measures.17, 20 For specific research applications, such as evaluating interventions to treat erectile dysfunction, the use of sex-specific measures is clear. In other settings, however, it may be desirable to assess the degree of sexual issues independent of sex. For example, describing the burden of sexual difficulties in long-term survivors would benefit from assessing men and women on comparable metrics when possible. Generating sex-neutral assessments is challenging and likely will require a modular approach to measure development.
From our review, only the UCLA PCI/EPIC, IIEF, and FSFI immerged as ‘legacy’ measures, that is, measures with extensive psychometric testing and sufficient clinical administration in oncology settings to help set the standard for the development of subsequent sexual function measures intended for use with cancer survivors. Indeed, in the last 15 years, the UCLA PCI/EPIC and the IIEF were used in approximately 66% of studies that examined the sexual function of individuals who had been treated for cancer. Although both measures are reliable and valid indicators of sexual function in men, there are important differences between these measures. The 20-item UCLA PCI was developed originally for use with the Rand 36-item Health Survey to yield a comprehensive quality-of-life assessment of men with prostate cancer46; the IIEF was developed with support from a pharmaceutical company for the purpose of evaluating multinational clinical trials of sildenafil citrate.47 Another distinction is that the UCLA PCI and its 26-item and 50-item EPIC versions specifically target symptoms associated with prostate cancer compared with the IIEF, which assesses sexual function only. Also, it has been demonstrated that the UCLA PCI can discriminate between older men with and without prostate cancer,26 and it has been used successfully in large prospective studies of prostate cancer conducted in the United States.48-50 The discriminant validity of the IIEF between men with and without cancer has not been reported, but the measure is able to discriminate between men receiving and not receiving sildenafil citrate for erectile dysfunction after radical prostatectomy51, and between men receiving or not receiving tadalafil after radiation therapy for prostate cancer.15, 52 Given their comparable levels of reliability and validity and use with cancer populations, the decision to use 1 or the other measure depends on research or clinical objectives as well as practical considerations. Measures that produce multiple conceptually precise subscales (eg, EPIC) may be suited better for research purposes because of the need to detect subtle intergroup differences over time; whereas measures with fewer, more global dimensions (eg, IIEF-5) may be adequate for clinical purposes (ie, for screening to help identify who may be having problems or as a catalyst to begin patient-provider communication about sexual function). In addition, because both the UCLA/EPIC and the IIEF are available at no cost, clinical use may favor the IIEF, which takes about 5 to 10 minutes to self-administer compared with the 20 to 30 minutes needed for the UCLA/EPIC versions. It should be noted that the version of the CaPS-SF for men will capture and test similar domains and items from both measures (in addition to those from other measures) with the goal of producing targeted, clinically relevant outcomes with the least possible administration and response burdens for all cancer sites.
Among the identified measures of sexual function in women that are used in oncology, only 1 measure appears to be emerging as a legacy measure, namely, the FSFI, which was developed by the IIEF originator, again with the support of pharmaceutical funding.30, 53 Used in studies of urologic,54 gynecologic,55-59 breast,60, 61 and rectal cancer survivors,62, 63 the FSFI appears to have undergone extensive psychometric testing and is able to discriminate between clinical and nonclinical populations.64 The 19-item FSFI takes less than 15 minutes to complete, uses a 4-week recall period, and is available at no cost.30 This measure has been used in clinical trials of sildenafil citrate65, 66 and vardenafil67 to evaluate partner satisfaction in women and, thus, may be a particularly useful measure in studies of cancers among men in which partner assessments are included as an outcome. The use of the FSFI in studies of women survivors of cancer also appears to be growing, as indicated by reports published subsequent to our CaPS-SF literature review.68, 69 The extent to which the FSFI is used in clinical settings to help evaluate and treat the sexual function of women survivors of cancer is unknown. Our CaPS-SF measure for women will capture and test domains and items similar to those found in the FSFI.
Unexpectedly, our literature review indicates that sildenafil citrate, which was approved by the US Food and Drug Administration in 1998 to treat erectile dysfunction, paved the way for the use of sexual function measures in oncology. Consequently, among cancer populations, the assessment of sexual function in men has outpaced the assessment of sexual function in women, an unanticipated finding given the decades of research documenting compromised sexual function after treatment for gynecologic and breast cancers. Although several well established measures of sexual function in women are available (eg, the Derogatis Sexual Functioning Inventory, Brief Index of Sexual Function for Women, and FSFI), it also was surprising that they have not been used as extensively as the UCLA PCI or IIEF.
A significant limitation of the existing measures is the lack of data demonstrating the validity of the measures for different cancer sites and across the continuum of cancer care. This limitation presents challenges for conducting meaningful cross-study comparisons across all cancer sites. Important exceptions are the UCLA PCI and the IIEF, as noted above, both of which have been used postdiagnosis through long-term follow-up care.
The current findings echo those of Cull,19 who concluded that no single, brief self-report measure of sexual function can be recommended for cancer clinical trials. Because sexual function is affected differentially by cancer site, cancer treatment, age, sex, partner status, sexual orientation, and cultural practices, researchers may need to develop their own measures to reflect better the characteristics of their targeted population. There are several advantages to developing a measure of sexual function that is sensitive, yet applicable, to a broader array of individuals, as discussed above. This review was undertaken as the first step in the PROMIS process for developing such a measure. Briefly, the remaining steps for our CaPS-SF subcommittee are to:
Refine the domain hierarchy based on the results of recently completed focus groups with cancer patients;
Review and standardize the items that remain from ‘binning and winnowing’ the approximately 1500 captured items from publicly available measures;
Write new items that address gaps identified through focus groups and cognitive testing;
Cognitively test the items with cancer patients and survivors;
Develop and refine the conceptual model informed by the above steps;
Collect self-report data from a large, diverse group of cancer survivors;
Evaluate the psychometric properties of the items and calibrate the items for the PROMIS-SF item bank; and
Create PROMIS-SF short-form instruments and implement CAT.
In subsequent reports, we will describe these next steps and detail the remaining processes as we work to develop a flexible and psychometrically robust measure of sexual function for use in clinical oncology settings, and, eventually, in other chronic disease settings. The final CaPS-SF product will be available internationally in the public domain by October 2009. National and international cooperative groups are encouraged to consider collaborating with the PROMIS initiative to assist with establishing further construct validity of the PROMIS-SF instrument in clinical trial settings. The complexity and resources needed to accomplish the CaPS-SF activities described above underscore the importance of support from the NIH Roadmap Initiative for Medical Research to develop psychometrically sound, patient-reported outcome measures.
Conflict of Interest Disclosures
Supported by grant U-5-U01-AR052186 from the National Institutes of Health.
- 2RiesLAG,MelbertD,KrapchoM, et al. eds. SEER Cancer Statistics Review, 1975-2005. Bethesda, Md: National Cancer Institute; 2008. Available at: http://seer.cancer.gov/csr/1975_2005. Accessed May 1, 2008.
- 3Institute of Medicine. Committee on Cancer Survivorship: Improving Care and Quality of Life. Washington, DC: National Academies Press; 2006.
- 6Institute of Medicine. Implementing Cancer Survivorship Care Planning: Workshop Summary. Washington, DC: National Academies Press; 2007.
- 15A randomized, double-blind, placebo-controlled, cross-over study to assess the efficacy of tadalafil (Cialis) in the treatment of erectile dysfunction following 3-dimensional conformal external-beam radiotherapy for prostatic carcinoma. Int J Radiat Oncol Biol Phys. 2006; 66: 439-444., , , .
- 25American Educational Research Association, American Psychological Association, National Council on Measurement in Education. Standards for Educational and Psychological Testing. Washington, DC: American Psychological Association; 1999.
- 31Development of a scale for assessing sexual function after treatment for gynecologic cancer. J Psychosoc Oncol. 1984; 2: 3-19., , .
- 40European Organization for Research and Treatment of Cancer (EORTC). EORTC quality-of-life questionnaires. Available at: http://groups.eortc.be/qol/questionnaires_modules.htm. Accessed December 28, 2007.
- 42Human Sexual Response. Boston, Mass: Little, Brown & Company; 1966., .
- 45A systematic review of the literature on female sexual dysfunction prevalence and predictors. Annu Rev Sex Res. 2004; 15: 40-172., , .
- 46University of California-Los Angeles. Prostate Cancer Index. Available at: http://www.uclaurology.com/conditions/Prost28.cfm. Accessed August 11, 2008.
- 65Sexual function and satisfaction in heterosexual couples when men are administered sildenafil citrate (Viagra) for erectile dysfunction: a multicentre, randomised, double-blind, placebo-controlled trial. Br Obstet Gynaecol. 2007; 114: 437-447., , , et al.