Table 2.

Comparisons of Polypharmacy Prevalence by Different Polypharmacy Definitions (n = 38,329)

	Definition 1 (novel definition)
	Yes, n (%)	No, n (%)	P
Definition 2			<0.0001
Yes	6355 (99.2)	49 (0.8)
No	13145 (41.2)	18780 (58.8)
Definition 3
Yes	19,048 (76.6)	5834 (23.4)	<0.0001
No	452 (3.4)	12,995 (96.6)

Definition-1 (new polypharmacy definition) is the simultaneous use of ≥5 different drug classes for a 60-day consecutive period; Definition-2 is the average number of drug classes that was 1 standard deviation above the mean in a 90-day period; Definition-3 is >5 different drug classes used in an arbitrary 90-day period.