OBJECTIVES: The strategy of priorization based on cost-effectiveness has been questioned because equity is not taken into account. The objective of this study was to develop a strategy of priorization based on the social welfare function (SWF), and to apply this method to decide allocation of resources between smoking cessation therapies and pharmacological treatments of hypercholesterolemia. METHODS: The social welfare function relates social welfare to the distribution of health gains between two patient groups, where the exact form depends on parameter e. The strategy of priorization based on SWF gives a higher priority to treatments associated with values of e consistent with that from the SWF. Parameter e of the SWF in Catalonia (Spain) was determined using multiple logistic regression analysis to assess preferences concerning the efficiency-equity trade-off in a group of health managers (n=140). RESULTS: The value of parameter e obtained was 2.26 (95 % CI: 1.07-2.89). This value was consistent with a non-utilitarian SWF. Values of e obtained for preventive interventions combining different smoking cessation methods for smokers and 20 - 80 mg/day lovastatin for individuals with hypercholesterolemia ranged from 0 to 2.9 in men and from 0 to 2.4 in women. The intervention using medical advice for smoking cessation in smokers and 20 mg/day lovastatin in individuals with hypercholesterolemia was associated with an e value of 2.9 in men and 2.4 in women, while interventions using nicotine substation therapies in smokers were associated with values of e < 1.0 in men and <0.5 in women. CONCLUSIONS: The strategy of priorization based on SWF gives a higher priority to 20 - 80 mg/day lovastatin for hypercholesterolemia than to nicotine substitution therapies for smokers. The strategy of priorization based on the SWF could give a higher priority to new treatments reducing the difference in health levels between groups of patients.