Method
Residents in Sweden aged 20–54 years in 2007, with stable employment between 2004 and 2007, were followed between 2005 and 2013 (n = 2,305,795). Employment at a workplace with staff reductions ≥18% between two subsequent years in 2007–2011 (n = 915,461) indicated exposure to, and timing of, downsizing. The unexposed (n = 1,390,334) were randomized into four corresponding sub-cohorts. With generalized estimating equations, we calculated the odds ratios (OR) of purchasing prescribed anxiolytics or sedatives within nine 12-month periods, from four years before to four years after downsizing. In order to investigate whether the groups changed their probability of purchases over time, odds ratios (OR) and their 95% confidence intervals (95% CI) were calculated contrasting the prevalence of purchases during the first and the last 12-month period within four time periods for each exposure group.