Validity of the Birth Certificate in the Epidemiologic Assessment of Facial Clefts

Abstract

The preoperative dental casts and birth certificates of 460 patients with facial clefts were compared to ascertain if there was any relationship between the extent of cleft and the completeness of birth certificate reporting. The results indicated that 29.4% of all clefts were not reported on the birth certificate. According to major type and subtype, the underreporting results were: isolated cleft lip, 35%; subgroups, 25-39%: cleft lip and palate, 14%; subgroups, 6-28%: isolated cleft palate, 48%; subgroups, 37-85%. In all subgroups the underreporting increased with decreasing severity of the cleft. The possible ramifications of the findings in the present study on other epidemiologic studies indicate that the researcher should exercise caution in assuming homogeneity of his sample if he utilizes the birth certificate as the means of collecting data for such studies.