Does knowledge of medication prices predict physicians' support for cost effective prescribing policies

British Columbia implemented a generic substitution (GS) and Reference Drug Program (RDP) to contain drug expenditures without negatively affecting health outcomes. Years after implementation, these policies remain controversial among physicians.

To assess British Columbia general practitioners' (GPs) opinions of RDP and GS stratified by knowledge of drug costs.

In telephone interviews, GPs ranked the economic and clinical appropriateness of drug policy options on a 5-point Likert scale. Responses to economic questions were stratified and compared according to the accuracy (+ $10 of the actual cost) of GPs' cost estimates for a 30-day supply of atorvastatin and omeprazole.

The majority of 210 interviewed GPs rated the economic appropriateness of GS and RDP positively (79% and 65%) but fewer rated them clinically appropriate (60% and 43%). Ratings for GS were more favorable than RDP, economically (mean=4.3 vs. 3.8, p=0.0005) and clinically (mean=3.7 vs. 3.1, p=0.006). GP's assessment of the therapeutic equivalence among ACE inhibitors and among CCBs correlated with their ratings of the respective RDPs (I=0.3, p=0.03, and I=0.4, p=0.02). GPs underestimated the price for omeprazole by C$28 (33%) and atorvastatin by C$28 (34%). GPs with accurate cost estimates were equally as likely to favorably rank the economic appropriateness of RDP as those with inaccurate estimates (mean = 3.7 vs. 4.0, p=0.0847). GS was assessed similarly (mean = 4.2 vs. 4.5, p=0.0712).

In British Columbia, the majority of GPs hold favorable opinions of GS and RDP; but, simply educating physicians about drug prices will not make them more supportive of cost-containment policies.