1. Almost all publicly insured children are insured by Medicaid. A small proportion of children are covered by state only programs.
2. We do not present the uninsured rate for infants because the Urban Institute reported uninsured rates for infants and pregnant women together.
3. That the median is 4 months is due in part to the pronounced "seam effect" in the reporting of health insurance status in the SIPP. Four months is the length of the reference period for each interview. Changes in insurance status are reported to occur disproportionately between interviews. In effect, most spells of fewer than 4 months duration and probably some with 5 or 6 month durations are reported in such a way that they appear to have exactly 4 month durations.
4. Wave 1 of the SIPP covered reference months between November 1989 and April 1990; wave 8 included months between February and August 1992.