Psychometric evaluation of self- and collateral timeline follow-back reports of drug and alcohol use in a sample of drug-abusing and conduct-disordered adolescents and their parents.

One hundred eighty-eight drug-abusing and conduct-disordered adolescents and their parents provided retrospective reports of the youths' frequency of alcohol and illicit drug use for each of the 6 months preceding their initial session in an outpatient treatment program. Youths' and parent reports of youths' drug and alcohol use for each month were similar. For marijuana and alcohol, frequency reports were related for each month, whereas hard drug reports were related only for the 4 months preceding intake. Relationships among alcohol and hard drug reports were strong during Months 1, 2, and 4 preceding intake, whereas strength of relationship among marijuana reports was similar throughout the 6 months.