Errors and correlates in parental recall of child immunizations: effects on vaccination coverage estimates.

OBJECTIVE: We evaluated the accuracy of parental recall of children's immunization histories as compared with provider records and examined how errors in parental recall correlate with sociodemographic characteristics. DESIGN: The validation study was part of a population-based household survey designed to assess immunization levels among Texas children under age 2 years. For 72% (n = 3278)- interviewers used vaccination records from the parent to copy dates for the diphtheria and tetanus toxoids and pertussis vaccine (DTP)- oral polio vaccine (OPV)- and measles- mumps- and rubella (MMR) shots. For parents without shot records (n = 1216)- interviewers asked about each vaccine- whether the child had received the shot- how many- and at what age. Of these- 85% (n = 1029) were validated with health provider records. RESULTS: Measured against provider records- only 34% of parents accurately recalled the number of DTP shots a child had. More often (42%) parents underestimated the number of DTP shots than overestima