“…13 These databases have served as the basis for many observational studies of medication adherence and are considered to be of high quality. 6,[14][15][16][17] To be eligible, subjects must have been at least 40 years of age and filled a new AHT prescription in one of the following pre-specified categories: β blockers, angiotensin-converting enzyme inhibitor, angiotensin receptor blocker, calcium channel blockers, or diuretic (thiazide and potassium-sparing). Those subjects who received a fixed-combination AHT product (two medications in a single pill/capsule) or dispensations for ≥2 distinct AHT medications on the index date were categorized as "combination therapy" (Appendix I).…”