Validating the Clinical Relevance of Alternative Stimulant Use Treatment Outcome Measures by Examining Their Association With 3-Month Follow-Up Outcomes

The lack of a consensus on empirically supported and clinically meaningful outcome measures for stimulant use disorders (SUDs) continues to undermine the development and evaluation of effective behavioral and pharmacological treatment options. The aim of this study was to evaluate the clinical relevance of four stimulant use treatment outcome measures (longest duration of abstinence [LDA], percent of negative urinalysis submitted, abstinent in the last 2 weeks of treatment, and three or more weeks of continuous abstinence) by exploring their utility via association with stimulant and alcohol use, employment and legal problems, and severity of psychiatric symptomatology collected at follow-up. Data used in these secondary analyses came from a multisite randomized contingency management treatment trial for SUDs (n = 441) conducted through the NIDA Clinical Trials Network. Multiple regression analyses were conducted to explore the association of four stimulant use treatment outcome measures and eight 3-month follow-up outcomes. The percent of negative urinalysis outcomes showed the most consistent performance compared to alternative outcomes, being significantly associated with better responses in all eight 3-month follow-up outcomes (β range: −169 to −241, p < .01). Both dichotomous outcome measures showed similar performances being significantly associated with four follow-up outcomes (β range: −159 to −203, p < .01). All outcome measures were consistently associated with better outcome responses at the 3-month follow-up, adding support to their clinical relevance and their adoption in SUD treatment trials. The two dichotomous outcome measures are reliable candidates to be used as endpoint outcomes, as recommended by the U.S. Food and Drug Administration (FDA). Public Health Significance The identification clinically meaningful indicators of treatment response can promote important advances in the development of more effective treatments for stimulant use disorders (SUDs). Our findings offer empirical support for the use of specific treatment outcome measures by determining their associations to clinically relevant 3-month follow-up outcomes.