RT Journal A1 Majumdar SR T1 COst sharing and the initiation of drug therapy for the chronically ill—invited commentary JF Archives of Internal Medicine JO Archives of Internal Medicine YR 2009 FD April 27 VO 169 IS 8 SP 748 OP 749 DO 10.1001/archinternmed.2009.41 UL http://dx.doi.org/10.1001/archinternmed.2009.41 AB Cost-related nonadherence (CRN) is common, and one-third of older adults take less medication than prescribed to reduce out-of-pocket costs.1 Common strategies to reduce out-of-pocket costs include splitting pills, skipping doses, or delaying refills, all secondary forms of nonadherence.1 Less attention has been paid to “primary” nonadherence, ie, not even filling the prescription. This strategy is the most effective way to reduce out-of-pocket costs, and primary nonadherence is practiced by 10% to 20% of patients.2