Table 3.

Adherence to Trial Medication, According to Treatment Group.^*

Outcome	Overall	81-mg Group	325-mg Group
Patients who switched aspirin doses — no./total no. (%)†	3479/14,391 (24.2)	516/7261 (7.1)	2963/7130 (41.6)
Patients who discontinued aspirin — no./total no. (%)‡	1299/14,391 (9.0)	506/7261 (7.0)	793/7130 (11.1)
Median days of exposure to assigned aspirin dose (IQR)	551 (304–834)	650 (415–922)	434 (139–737)
Median days of exposure to any aspirin dose (IQR)	658 (426–932)	670 (439–944)	646 (412–922)

^*Trial medication adherence is based on patient report at visits every 3 or 6 months. All reported information from one completed visit to the next was used. Dose switching or discontinuation that occurred after the last reported aspirin dose would have been missed (8.2% of the patients in the 81-mg group and 9.6% of those in the 325-mg group were alive at the end of the trial but did not complete an end-of-trial visit).

^†Dose switching is defined as reporting a dose of aspirin different from the randomized dose at one or more postrandomization trial encounters.

^‡If Discontinuation is defined as reporting “No” to the trial question “Are you regularly taking aspirin?” at one or more postrandomization trial encounters.