• Functioning;
  • concordance;
  • inter-rater reliability;
  • adolescence

Objective:  Adolescents’ functional impairment has become increasingly important as a criterion for diagnosis and service eligibility as well as a target of therapeutic intervention in mental health settings. This study examines three critical issues in measuring functioning: 1) agreement between parent and adolescent reports of functioning, 2) explanations for disagreement, and 3) clinicians’ ratings of functioning compared with parent and adolescent reports.

Methods:  Agreement between parent and adolescent reports of functioning was estimated using the kappa statistic and conditional agreement in a sample of 258 adolescents. Rates of and reasons for expected disagreements between informants were explored in semi-structured interviews (n = 43). ANOVA was calculated for clinician ratings for parent–adolescent pairs categorized on the basis of their agreement or disagreement on impairment. Finally, the independent contribution of parents’ or adolescents’ reports of impairment on clinician ratings of functioning was examined.

Results:  From 12% to 97% of problems reported by one informant were denied by the other. Agreement was particularly poor for questions about relationships with friends, peers’ delinquent behaviors, and leisure activities. On average, parents and adolescents were more likely to expect the other would agree with their ratings rather than disagree. Reasons for disagreement included: 1) differences in how parents and adolescents interpreted questions; 2) lack of parental awareness of adolescents’ behaviors; and 3) different thresholds for what is considered problematic. Results also demonstrated that clinicians perceive problems reported only by parents as somewhat more serious than problems reported only by adolescents.

Conclusions:  Implications for diagnosis, treatment planning and outcomes measurement are discussed.