The Polysubstance Assessment Tool: Reliability, acceptability and feasibility of a novel measure of polysubstance use

Abstract Background and aims There are currently no brief quantitative assessments that capture the drug patterns of people who engage in use of more than one drug on the same day or simultaneously. The current study examined the retest reliability, acceptability and feasibility of a new quantitative assessment to measure polysubstance use. Design A tool for assessing simultaneous and same‐day polysubstance behaviors, the polysubstance assessment tool (PAT) was developed in interviewer‐administered and electronic self‐administered formats. Participants were allocated 1:1 to receive either version of the PAT and returned one to three days later to repeat the assessment. Setting New York City, New York, USA. Participants Adults (18 + years, n = 115) who reported use of more than one drug per day in the last 30 days. Measurements Test–retest reliability estimates for dichotomous items were assessed using Cohen's kappa, Gwet's Agreement Coefficient 1 (AC1) and percent agreement. Continuous items were assessed with two‐way mixed effects intraclass correlations. Bivariate analyses examined acceptability using nine Likert‐type survey questions. Feasibility was examined via time to completion. Findings Overall reliability was moderate to excellent Gwet's AC1 range 0.70–0.96; intraclass correlation (ICC) range 0.62–0.88. Reliability was higher for simultaneous polysubstance use (Gwet's AC1 = 0.90) as compared with same‐day (Gwet's AC1 = 0.70). Acceptability was high, with no statistically significant difference between the self‐ and interviewer‐administered versions of the tool. Median time to completion was 7 minutes, and was statistically significantly lower for the self‐administered tool (median = 5 minutes) compared with the interviewer‐administered version (median = 8 minutes) ( P < 0.001). Conclusions A new polysubstance assessment tool appears to have good reliability and can be considered by researchers seeking a quantitative measure of polysubstance use behaviors given its simplicity, high acceptability and quick completion time.