Fig. 1

Concentration indices for neonatal and postneonatal mortality rates and their six associated factors, according to wealth index distribution. Concentration indices for neonatal and postneonatal mortality rates and the proportion of infants classified as having low birth weight, the proportion of deliveries occurring in hospitals, the mean maternal age, the proportion of households covered by any insurance, the proportion of households headed by men, and the proportion of literate women of reproductive ages are shown during the 4 time intervals under study. The levels of uncertainty for these indices are also presented in the graph. As mentioned previously, positive concentration index values indicated a positive correlation between wealth status and the variable of interest, whereas a negative concentration index value indicated a negative correlation. A concentration index of 0 indicated absolute equity in the distribution of study variable in respect to wealth status