PCV42: PATIENTS' WILLINGNESS TO PAY FOR PHARMACIST MANAGED WARFARIN THERAPY AT COMMUNITY PHARMACIES

Abstract

OBJECTIVES: This study determined the benefits of pharmacist managed warfarin therapy (PMWT) at community pharmacies by the contingent valuation (CV) method. Benefits of PMWT in clinic have been documented. These are reduction in hospitalizations, emergency room visits and thromboembolic events due to side effects of inappropriate dosing and monitoring. However, these benefits were never measured from patient's perspective using CV method. This study elicited willingness-to-pay (WTP) values for PMWT from community pharmacy patients. METHOD: A self-administered 24 question CV survey was mailed to 2800 patients' homes. These patients were selected from files in community pharmacies or a rural health plan. They were divided into warfarin clinic (ex post) and non-warfarin clinic (ex ante) groups. A payment card method with visual aid charts elicited WTP values in form of out-of-pocket (OOP) expense and additional insurance premium (INS) for PMWT with six probabilities for success (3 probabilities for reduction in hospitalizations & 3 probabilities for reduction in blood clot events). RESULTS: Five hundred and thirty patients (393 usable) responded. Overall mean WTP values for PMWT in the form of OOP or INS were significantly greater than zero. The monthly mean OOP WTP amounts for 28% blood clot event reduction and 26% hospitalization reduction were $17.19 ± 15.57 and $19.26 ± 17.56 respectively. The monthly mean INS WTP for the same probabilities were $11.97 ± 13.66 and $12.66 ± 14.63 respectively. Regression analysis identified that annual household income, selection of health plan with PMWT and attitude towards the health plan's inclusion of PMWT were significant predictors for OOP scheme and only annual household income and selection of health plan with PMWT for INS scheme. CONCLUSION: Patients were able to assign WTP values to different sizes of health gains. Range bias and inconsistency of choice were detected from this sampled population.