Timeliness for vaccination according to the expanded immunization program in children under 6 years of age in Colombia between 2014 and 2019

The aim was to estimate the vaccination timeliness defined as the proportion of children under 6 years of age who received their immunization in the time range established by the Colombian Expanded Immunization Program (EIP). A retrospective cohort study that collected reports of vaccination opportunities between 2014 and 2019 provided by the Ministry of Health. Age, sex, city, ethnicity, health system affiliation regimen, vaccine applied, and timing of vaccination were considered for the time range under study. A total of 3,370,853 immunized children were included from all regions of the country. More than 80% of children had a timeliness to get most vaccines. The exceptions were yellow fever (17%) and seasonal influenza (42%). No differences in timeliness were found according to geographic region or by health system affiliation regime, but the average timeliness for all vaccines of children of the indigenous population (65.8% ±18.4%) was lower than that of the rest of the population (78·6% ± 19·3%) (<i>p</i> = 0·021). The timeliness for vaccination under the EIP of Colombia is high, with proportions of 72-96%, but intergroup differences were identified, mainly lower timeliness among indigenous people. These findings warrant improvement strategies that would guarantee the immunization of the entire child population.