Immunization coverage and infant mortality rate in developing countries

We examined whether immunization coverage (IMC) is one of the predictors of infant mortality rate (IMR), as a single indicator representing the availability of primary health care (PHC) services in developing countries. Multiple regression analysis showed that partial correlation coefficients for IMR with immunization coverage (-0.224), logarithm of per capita GNP (-0.294), total fertility rate (0.269), and adult literacy rate (-0.325) were all statistically significant (p < 0.001) in 97 developing countries which make up more than 97% of the population in all the developing countries of the world. Multiple correlation coefficients of IMR with these four variables in 97 countries was 0.921. Thus, more than 80% of variation of IMR in developing countries were explained by the variation of the four variables. The study also showed that IMC was well correlated (simple correlation) with the four indicators of the availability of primary health care services; access to local care (0.730), care of pregnant women (0.603), delivery care (0.666), and infant care (0.553), all of which were statistically significant (p < 0.001) in the 48 developing countries which make up 42% of the population of all developing countries. Multiple correlation coefficients of these four variables was 0.787. About 60% of the variation of IMC will be explained by the variation of the four variables. Thus we conclude that immunization coverage is one of the main predictors of the infant mortality rate. It represents one of the health intervention components which can be used as a proxy indicator of the availability of PHC service in developing countries.