Measurement invariance and other psychometric properties of the Short Inventory of Problems (SIP-2R) across racial groups in adults experiencing homelessness and alcohol use disorder.

Objective: People experiencing homelessness are disproportionately impacted by alcohol-related harm. Racially minoritized groups are disproportionately represented in the homeless population and are likewise disproportionately impacted by alcohol-related harm. Most alcohol outcome measures have not been adequately psychometrically studied in this marginalized population and across racial groups. This study documents psychometric properties, including measurement invariance, reliability, and convergent validity, of a measure of alcohol-related harm, the Short Inventory of Problems (SIP-2R), across Black, North American Indigenous (NAI), and White adults experiencing homelessness and alcohol use disorder (AUD).
Method: Adults experiencing homelessness and AUD who had participated in one of two randomized controlled trials of harm-reduction treatment ( N = 493; NAI = 205, Black = 125, and White = 163) were included in this psychometric study of the 15-item SIP-2R.
Results: Multigroup confirmatory factor analysis (MGCFA) indicated that a model comprising one general alcohol-related harm factor overarching five factors, showed close fit and partial scalar invariance, χ ²(329, N = 493) = 624.902, p < .001, comparative fit index (CFI) = .966, root-mean-square error of approximation (RMSEA) = .074, 90% CI [.066, .083], standardized root-mean-square residual (SRMR) = .063, confirming acceptable measurement equivalence across racial groups. The SIP-2R showed internal consistency (α = .94, ω = .95) and convergent validity, that is, positive correlation between the total SIP-2R score and the number of drinks consumed the heaviest drinking day, ρ(490) = .30, p < .001.
Conclusion: This study provided support for the internal consistency, convergent validity, and cross-group measurement equivalence of the SIP-2R for NAI, Black, and White adults experiencing homelessness with AUD. (PsycInfo Database Record (c) 2023 APA, all rights reserved).