The study finds significant positive insurance effects on preventive care for children aged 3–24 months in the form of the child having received all the age-appropriate immunizations. Several studies have previously shown an increase in child visits to physicians with insurance gain in both developed and less developed settings. However, to my knowledge, this is one of the first studies to show an improvement in specific preventive care measures with insurance for young children who have some access to well-child care in the study populations. Comparing uninsured and insured children who were attending the same paediatric clinic for routine well-child care and adjusting for several relevant observable characteristics is a unique strength of this study. This design accounts for potential differences in immunization schedules and care standards between paediatric care practices that may also vary in their distributions of insurance status and other insurance-related child-level characteristics as well as in unobserved area-level factors affecting the supply of and demand for immunizations.