TABLE 4.

Statin Adherence in the Pre- and Post-index Periods in Statin Adherence Cohort (N = 949)

	Overall (N = 949)	Guideline (n = 588)	Historical (n = 361)	P Valuea
Pre-index period
Statin PDC, mean [SD]	0.82 [0.22]	0.83 [0.20]	0.80 [0.23]	0.018
Nonadherent,b n (%)	301 (31.7)	177 (30.1)	124 (34.3)	0.172
Adherent,b n (%)	648 (68.3)	411 (69.9)	237 (65.7)
Post-index period
Statin PDC, mean [SD]	0.79 [0.25]	0.81 [0.24]	0.75 [0.27]	< 0.001
Nonadherent,b n (%)	351 (37.0)	197 (33.5)	154 (42.7)	0.005
Adherent,b n (%)	598 (63.0)	391 (66.5)	207 (57.3)

^a Guideline and historical groups were compared using chi-square test.

^b Nonadherent was defined as PDC < 0.80, and adherent was defined as PDC ≥ 0.80.

PDC = proportion of days covered; SD = standard deviation.