Sensitivity of birth certificate reports of birth defects in Atlanta, 1995-2005: effects of maternal, infant, and hospital characteristics.

OBJECTIVES

We assessed variations in the sensitivity of birth defect diagnoses derived from birth certificate data by maternal, infant, and hospital characteristics.

METHODS

We compared birth certificate data for 1995-2005 births in Atlanta with data from the Metropolitan Atlanta Congenital Defects Program (MACDP). We calculated the sensitivity of birth certificates for reporting defects often discernable at birth (e.g., anencephaly, spina bifida, cleft lip, clubfoot, Down syndrome, and rectal atresia or stenosis). We used multivariable logistic regression models to examine associations with sociodemographic and hospital factors.

RESULTS

The overall sensitivity of birth certificates was 23% and ranged from 7% for rectal atresia/stenosis to 69% for anencephaly. Non-Hispanic black maternal race/ethnicity, less than a high school education, and preterm birth were independently associated with a lower probability of a birth defect diagnosis being reported on a birth certificate. Sensitivity also was lower for hospitals with > 1,000 births per year.

CONCLUSIONS

The underreporting of birth defects on birth certificates is influenced by sociodemographic and hospital characteristics. Interpretation of birth defects prevalence estimates derived from birth certificate reports should take these issues into account.