[Potential coverage and real coverage of ambulatory health care services in the state of Mexico. The case of 3 marginal communities in Atenco and Chalco].

Less than a third of the non-insured population studied through a sample in the State of Mexico was covered by the Institute of Health of the State of México. This low coverage was observed in spite the fact that health services were available within 2 kilometer radius. 33 per cent of the non-insured preferred to utilize other services within their own community, and 24 per cent of them traveled to bigger localities to receive care. These results suggest that to attain adequate coverage, utilization patterns should be investigated so that health services can meet the needs of the target population.