[Medical insurance coverage in Mexico].

OBJECTIVE: To present estimates of health insurance coverage in Mexico and discuss the differences among some sources of information.

MATERIAL AND METHODS: Based on a national survey performed in 2002, the percentage of insurance coverage was estimated by state, rural condition, and expenditure level.

RESULTS: The percentage of the population without medical insurance is 59.9%. The main insurance institution is the Mexican Institute for Social Security (Instituto Mexicano del Seguro Social, IMSS), with a coverage of 29.5%. Private insurance agencies cover 1.5% of the total population. There are huge differences in insurance coverage by state, expenditure level and social exclusion level.

CONCLUSIONS: Data on insurance coverage provided by Mexico's main social security institution differ from that obtained through population-based studies. Some of these differences may be due to probabilistic reasons and others to macroeconomic changes. However, these reasons had not been sufficiently explored. In depth studies are needed in order to explain the observed differences.