guided by established classifications.(6) Specific classifications of benzodiazepine agents and Z drugs, based on previously published definitions, are shown in eTable 2.(34, 35) Furthermore, we collected data on age, sex, relationship of patient to the primary beneficiary, and insurance status. Because our cases are self-matched in case-crossover design, our models did not warrant adjustment for time-invariant measured confounders (e.g., sex or race).
