Note on the reliability and validity of mothers' retrospective reports of their children's birthweights.

Using data from the 1973, 1976, and 1982 National Survey of Family Growth Studies, mothers' retrospective reports of their children's birthweights are compared across surveys and with vital registration data. Comparisons focus on estimated levels for blacks and whites, and on the effects of possible determinants. Despite the fact that nonresponse is more common for blacks, especially for births occurring at dates more distant from the surveys, results show that retrospective reports of low birthweight (less than 5.5 pounds) provide valid and reliable estimates of trends and differentials.