[Evaluation of a program: cost/benefit analysis]

The authors evaluate a program of peripheral obtention of analytical samples during a 37-month period in the Granada province, which it has been able to extend to 40.44% of the population. An analysis of the cost/benefit ratio and the efficacy in the implantation of the program (77.78%) during that period was carried out. The results were compared with those achieved with this program in other Spanish provinces. Finally, an indicator was proposed (expected mean number of users per 1000 inhabitants and month) which might permit to know in advance the effectiveness of the implantation of the Program in a given area.