Table 3.

Persistence duration and associated hazard ratio for the changed and continued cohorts

Persistence duration a , days, median (range)			Hazard ratio b (95 %CI)
Changed to generic	Continued brand	P value	Unadjusted	Adjusted c
180 (14~180)	180 (28~180)	0.076	0.69 (0.44-1.08)	0.97 (0.61-1.55)

^aPersistence was measured as the number of continuous days from index date to discontinuation in the 180-day.

^bCox proportional hazard model.

^cAdjusted baseline covariates included adherence in pre-index date (baseline adherence) (PDC≧80 %), duration of use of atorvastatin prior to index date, prescribing medical establishment, comorbidities such as hypertension, arrhythmia, and calcium channel blocker.