Construct and differential item functioning in the assessment of prescription opioid use disorders among American adolescents.

Abstract

OBJECTIVE:To examine the psychometric properties of diagnostic criteria for prescription analgesic opioid use disorders (OUDs) and to identify background predictors of a latent continuum for OUD liability. METHOD:Data were drawn from the adolescent sample of the 2006 National Survey of Drug Use and Health. Item response theory (IRT) and multiple indicators-multiple causes methods were used to examine DSM-IV criteria for OUDs in a subsample of adolescents who reported nonmedical prescription opioid use in the past year (N = 1,290). RESULTS:Among nonmedical users of prescription opioids, the criteria of OUDs were arrayed along a single continuum of severity. All abuse criteria were endorsed at a severity level higher than D1 (tolerance) and D5 (time spent) but lower than D3 (taking larger amounts) and D4 (inability to cut down). Differential item functioning in reports of dependence symptoms across adolescents' sex and race/ethnicity were identified: withdrawal, time spent, and continued use despite medical or psychological problems. Adjusting for the effects of differential item functioning and the demographic variables examined, female subjects were more likely than male subjects to exhibit a higher level of OUD liability. CONCLUSIONS:Study findings do not support the DSM-IV's current hierarchical distinction between abuse of and dependence on prescription opioids. Abuse symptoms in adolescents are not necessarily less severe than those of dependence. There is evidence of some differential item functioning in the assessment of OUDs.