Validation of the OWLS, a screening tool for measuring prescription opioid use disorder in primary care

Objective. The OWLS is a screening tool for prescription opioid use disorder designed for use in primary care. This study aimed to confirm the optimal wording, scoring methods, and cutoff for the OWLS. Design and Setting. Crosssectional analysis of an online sample. Subjects. Participants comprised those with chronic noncancer pain who regularly used prescription opioids. Methods. Eligible participants self-completed an online version of the OWLS prescription opioid use disorder screening tool and the Composite International Diagnostic Interview Substance Abuse module. Receiver operating characteristics were calculated for three scoring methods for the OWLS, and these were compared with DSM-5 classification of any use disorder and moderate to severe opioid use disorder. Results. Among the sample (N = 324), utilizing scoring method (i) (i.e., positive endorsement response option “a little bit”) and a cutoff of 3 increased the percentage of correctly classified participants, with concurrent increases in specificity and decreases in false discovery rate, and false positive rate. Conclusion. OWLS utilizing scoring method (i) with a cutoff of 3 was shown to be the optimal version and scoring method of this tool. This represents a time-efficient, simple scoring method, allowing for quick and accurate screening for opioid use disorder to occur.