TABLE 5.

Multivariate Results for Persistence, Adherence, and Health Care Cost Among Fixed 3-Tier Plans

Variables	Persistencea HR (P Value)	Adherenceb OLS (P Value)	Health Care Costc GLM (P Value)
Maximum copay ($10 increments)	1.11 (0.0000)	-0.03 (0.0000)	0.95 (0.1945)
Maximum copay, squared	0.99 (0.0012)	0.00 (0.0007)	1.00 (0.5805)
Age (years)	0.99 (0.0000)	0.01 (0.0000)	1.01 (0.0000)
Male	0.91 (0.0000)	0.04 (0.0000)	1.03 (0.1507)
Fully insured (reference: self-insured)	1.01 (0.6870)	0.00 (0.2796)	0.93 (0.0011)
High deductible medical plan	1.11 (0.0000)	0.00 (0.4221)	0.97 (0.4325)
Baseline patient contribution, $	1.00 (0.2614)	0.00 (0.0000)	1.00 (0.0000)
Baseline payer, $	1.00 (0.0001)	0.00 (0.3395)	1.00 (0.0000)
Unique prescription medications	1.00 (0.0000)	0.00 (0.0010)	1.04 (0.0000)
Charlson comorbidity score	-1.01 (0.0302)	-0.00 (0.3054)	1.08 (0.0000)
Baseline DCSI	1.03 (0.0000)	-0.01 (0.0000)	1.05 (0.0000)
Constant	0.00 (0.0000)	0.49 (0.0000)	11619.02 (0.0000)

^aParametric regression survival models were used to model time to discontinuation, adjusted for covariates listed.

^bOrdinary least squares regression models were used to evaluate medication adherence, adjusted for covariates listed.

^cGeneralized linear models were used to calculate estimated cost ratios, adjusted for covariates listed.

DCSI = Diabetes Complications Severity Index; HR = hazard ratio; OLS = ordinary least squares; GLM = generalized linear models.