In the regression model comparing covered children separately by insurance type to uninsured children enrolled at the same study clinic as the insured children, and adjusting for all relevant observed characteristics, public insurance is significantly associated with an increase in the probability of adequate immunization status by 3.5 percentage points. Private insurance has a smaller and insignificant positive effect. In the model evaluating the effect of any insurance (combining public and private insurance), insurance is positively associated with adequate immunization status, but the effect is statistically insignificant (P = 0.1).