Table 2.

Predictors of polypharmacy among 698 participants in the Longitudinal Assessment of Manic Symptoms^a

Block	df	Nagelkerke R2 change	p
Site	3	.04	<.001
Demographic characteristics	4	.07	<.001
Insurance and family history	3	.01	.241
Specific diagnoses	8	.09	<.001
Severity	4	.05	<.001
Provider type	3	.05	<.001

^aBased on logistic regressions predicting use of two or more medications concurrently. Sensitivity analyses using Poisson regression to predict the count of the total number of medications found the same predictors and patterns, with slightly smaller p values for several due to the greater variance in the dependent measure. Final model: Total R²=25, Nagelkerke R² change=.30, p<.001