Equivalence of family functioning and externalizing behaviors in adolescent substance users of different race/ethnicity.

The Brief Strategic Family Therapy for Adolescent Drug Abuse clinical trial of 480 adolescents boys and girls aged 12 to 17 years and their parents was designed to maximize the chance that a sufficient number of Hispanic and Black adolescents would be included to allow valid subgroup comparisons. Examination of measurement invariance is an important step to ensure valid analysis. Two construct areas important to the analysis of trial results, adolescent problem behaviors, and family functioning showed a high degree of measurement invariance, which allowed valid comparisons of mean baseline differences across groups. Results showed that Black families had significantly higher initial levels of family functioning and lower levels of adolescent externalizing behaviors than either Hispanic or White non-Hispanic families. This pattern is consistent with an increased likelihood of referral of Black adolescents with more severe problems to restricted setting rather than to outpatient drug abuse treatment. This possibility highlights the importance of considering differing baseline characteristics of subgroups prior to assessing differential treatment effectiveness to prevent confounding.