Psychometric performance of the perceived stigma of substance abuse scale (PSAS) among patients on methadone maintenance therapy in Vietnam

Substance use stigma: A systematic review of measures and their psychometric properties

Background

Instruments to measure substance use stigma are emerging, however little is known regarding their psychometric properties. While research has evolved to view substance use stigma as a context sensitive international phenomenon that is embedded within cultures, validated self-report measures are lacking and comprehensive reviews of the existing measures are extremely limited. In this systematic review of substance use stigma and shame measures, we aim to contextualize results from existing research, lay the groundwork for future measurement development research, and provide a thorough resource for research scientists currently designing studies to measure substance use stigma.

Methods

We searched three databases using Boolean search terms for psychometric evaluations of measures of substance use stigma and shame and evaluated the quality/psychometric properties using an adaptation of the COnsensus-based Standards for the selection of health Measurement Instruments (COSMIN) systematic review guidelines.

Results

We identified 18 measures of substance use stigma. Overall, most measures had minimal psychometric assessments and none of the measures met all domains of the COSMIN measure quality criteria. However, most studies reported satisfactory factor analyses and internal consistency scores.

Conclusions

Most measures of substance use stigma and shame had psychometric assessment across a limited range of criteria and no measures of structural substance use stigma were found. The most reported psychometric properties were structural validity and convergent validity. We suggest future researchers investigate test-retest reliability and cross-cultural validity for existing substance use stigma measures, as well as develop and evaluate novel measures assessing structural stigma of substance use.

Correlates of Perceived Discrimination Related to Substance Use Disorders Among Patients in Methadone Maintenance Treatment

This study sought to examine demographic, treatment-related, and diagnosis-related correlates of substance use disorder (SUD)-related perceived discrimination among patients receiving methadone maintenance treatment (MMT). Participants were 164 patients at nonprofit, low-barrier-to-treatment-access MMT programs. Participants completed measures of demographics, diagnosis-related characteristics (Brief Symptom Inventory (BSI-18) and Depressive Experiences Questionnaire (DEQ)), and treatment-related characteristics. Perceived discrimination was measured on a seven-point Likert-type scale ranging from 1 ("Not at all") to 7 ("Extremely") in response to the item: "I often feel discriminated against because of my substance abuse." Given the variable's distribution, a median split was used to categorize participants into "high" and "low" discrimination groups. Correlates of high and low discrimination were analyzed with bivariate and logistic regression models. Ninety-four participants (57%) reported high SUD-related perceived discrimination. Bivariate analyses identified six statistically significant correlates of SUD-related perceived discrimination (P < .05): age, race, age of onset of opioid use disorder, BSI-18 Depression, DEQ Dependency, and DEQ Self-Criticism. In the final logistic regression model, those with high (versus low) SUD-related perceived discrimination were more likely to report depressive symptoms and be self-critical. Patients in MMT with high compared to low SUD-related perceived discrimination may be more likely to report being depressed and self-critical.