Co-use of alcohol and prescription opioid medication increases risk for harmful and potentially fatal health effects (e.g., overdose). Behavioral intentions (i.e., the immediate antecedent of corresponding behavior according to the Theory of Planned Behavior) are important in prediction of substance use, and a valid measure assessing intentions to co-use alcohol and opioids is needed to identify individuals at-risk for harmful substance use. The goal of the current study was to develop and conduct the psychometric validation of a six-item Intentions to Co-Use Alcohol and Opioids (ICAO) scale. Participants included 261 (Mage = 38; 64% male) past-month drinkers with a current opioid prescription and chronic musculoskeletal pain who completed a targeted online survey. Confirmatory factor analysis indicated that a single-factor structure provided good model fit (Bollen-Stine bootstrap p = .121). Moreover, the ICAO demonstrated high internal consistency (α = .96) and was correlated with measures of alcohol and opioid use/co-use. These findings provide support for the single-factor structure, reliability, and concurrent/convergent validity of the ICAO among individuals who endorse alcohol use, opioid use, and chronic musculoskeletal pain. The ICAO may offer clinical utility as a tool to identify individuals at greater risk of potentially fatal co-use of alcohol and opioid medications.
Keywords: Alcohol; chronic pain; co-use; opioids; pain.