Concordance between Self-Reported Drug Use and Urinalysis in a Sample of Black American Women

Background: Obtaining accurate drug use data is important in the field of substance use research. Urinalysis, considered gold standard, can be costly or infeasible, whereas self-report is quick and easy, but susceptible to imperfect recall or misrepresentation. It is important to determine the concordance between self-report and urinalysis, and better understand the contexts and participant characteristics that influence self-report accuracy. The current study aims to assess this concordance for marijuana and cocaine in a sample of Black American women, some with criminal justice exposure, and to investigate predictors of non-concordance. Methods: In this longitudinal study, a sample of Black American women were recruited from community, prison, and probation settings. Self-report drug use and urine drug screens were obtained at 6-, 12-, and 18-month follow-ups, allowing for the calculation of concordance. Generalized linear mixed models were used to assess participant characteristics that predicted non-concordance (both false positives and false negatives). Results: In general, there was agreement between self-report and urinalysis results for both marijuana and cocaine. Baseline drug use status was the most consistent predictor of non-concordance. Individuals recruited while on probation were more likely to have false negative results and less likely to have false positive results. Additionally, concordance rates for marijuana increased over the follow-up period. Conclusions: Self-reported marijuana and cocaine use are accurate measures of actual drug consumption in a sample of Black American women with a variety of criminal justice interactions.