Our analytic sample was derived from a previously described cohort of 304 676 individuals in the US, aged 12 to 64 years, who had prescription drug coverage, a diagnosis of OUD, at least 1 OUD claim during enrollment, and continuous insurance enrollment.20 Figure 1 depicts the derivation of our final analytical sample. Because we used a case-control design, we limited analyses to the 29 157 individuals with alcohol-related acute events (ie, 275 519 individuals were ineligible because they did not experience the outcome of interest). The first event for each person subsequent to initiating OUD treatment was defined as the index event. The index event date was used to generate a longitudinal data set at the day level containing all days in which a given individual was observed (ie, covered by insurance), up to 1 year before and after the index event; that is, the final data set contained 1 record per day per person, with the units of observation being person-days. Our decision to choose a 2-year maximum observation window was guided by the mean length of time individuals
