Evaluación de tecnologías sanitarias

Abstract

This thesis is composed of three substantial chapters, corresponding with three projects dealing with different topics on economic evaluation, but with one aspect in common, that is, the reduction of the uncertainty in healthcare decision making. Two are empirical cost-effectiveness studies in areas of public health: an evaluation of a physical exercise program in perimenopausal women, and an evaluation of options for a screening program for risk of cardiovascular disease. The third chapter is a review and classification of costing methods for economic evaluation. The first chapter studies the cost-effectiveness of an exercise intervention in perimenopausal women from Granada aged between about 45 and 64. The 150 women were randomly assigned to either an exercise intervention group (N = 74) or to control group (N = 76). The intervention group was subject to an exercise intervention program of 4 months of duration specially designed for perimenopausal women. Both decision model and numerous sensitivity analysis demonstrated that physical exercise improves the quality of life and decreases the costs, although the differences were not statistically significant. The exercise program was cost-effective. The second chapter assessed the cost-effectiveness of different screening strategies for cardiovascular disease in England and Andalusia. The data were obtained from the EPICCVD study that recruited more than 500,000 people in 10 European countries, giving up to 15 years follow-up. The study identified more than 16,000 cases of coronary heart disease and 11,000 cases of stroke. To estimate the risk of each individual, two strategies were considered: the Framingham risk score, which estimates the risk of having a cardiovascular event at 10 years, and a novel approach based on the Framingham risk score adjusted for age and sex. The costs and benefits of alternative methods of identifying high-risk individuals in primary care and treating them with statins to reduce their cardiovascular risk were modelled (probabilistic Markov model). Both the base case model and the sensitivity analysis show that the novel approach based on the age adjusted Framingham risk score is more cost-effective regardless of sex, age and geographic area. The third chapter offer a classification of different costing methods used in economic evaluations. For better clarification of terminology, a pragmatic glossary of terms is proposed. A scoping review was conducted. A total of 21 studies were included yielding 43 costing analysis. The most common analysis was top-down micro-costing (49%), followed by top-down gross-costing (37%) and bottom-up micro-costing (14%). In general, substantial inconsistencies in the costing methods were found. The information regarding unit cost calculation is lacking. The convergence of bottom-up and top-down methods might be a hot topic for discussion in next decades.