Birth certificates are not effectively capturing birth defects, according to a new study conducted by public health researchers.
Their findings, “Evaluation of the Sensitivity and Accuracy of Birth Defects Indicators on the 2003 Revision of the U.S. Birth Certificate: Has Data Quality Improved?” has been published in Paediatric and Perinatal Epidemiology.
USF College of Public Health researchers, Jean Paul Tanner, Diana Sampat, Dr. Jennifer Marshall, Dr. Russell Kirby, and COPH alumnus Dr. Jason Salemi are co-authors with other public health researchers on the publication.
Changes on how birth defects are recorded on birth certificates have been ongoing since 1968, according to Salemi, the study’s lead author. In 2003 in particular, revisions were made to restrict to collection of birth defects that are readily identifiable within the first 24 hours after birth.
“Because the 2003 revision restricted to birth defects that should be easy to identify, we thought maybe the current version of the birth certificate would do a better job in capturing infants born with birth defects,” Salemi said.
Using birth certificate data and comparing it to confirmed cases of birth defects in the statewide Florida Birth Defects Registry, researchers assessed the sensitivity and positive predictive value of birth defect indicators on birth certificates.
Results indicate that, despite recent revisions, many children born with serious birth defects are not being identified on birth certificates.
“What we ultimately found is that the birth certificate is only capturing about 1 in every 5 infants born with one of these major birth defects,” Salemi said. “Although we did find variation depending on what defect it was, such as spina bifida, Down Syndrome or gastroschisis, even at its best the birth certificate was only capturing 1 in every 2 infants with the birth defect—at its worse, 1 in every 20.”
Salemi said that using birth certificates to examine birth defects is appealing to researchers because of their low cost and universal reach, but it’s not enough to capture all or even most of the infants who are actually born with a defect.
“If a study is being proposed in which the only source of birth defects data is the birth certificate, that study is of too poor of quality and must be supplemented with other data sources,” he said.
The researchers do not recommend the use of birth certificates as a source of birth defects data without case verification strategies, as the efforts to restrict the 2003 revision of the birth certificate to defects identifiable at birth have not improved the likelihood that birth certificates will identify infants born with those defects.
Salemi, assistant professor in the Department of Family and Community Medicine at Baylor College of Medicine, has worked for more than 10 years with Tanner and Kirby in the COPH Department of Community and Family Health’s Birth Defects Surveillance Program.
He said that there is a vast difference in the quality of data noted on birth defects, varying greatly by hospital.
“We have some hospitals doing a really good job in filling out the birth certificates for major birth defects and some hospitals not doing it at all,” he said. “It depends on what protocols are in place at the hospital and the fact that the primary purpose of birth certificates is not to capture information on birth defects.”
He said he hopes this research will highlight the need for supplementing vital statistics records like birth certificates with other data sources and primary data collection when investigating birth defects.
“We’re hoping, at a minimum, this study increases the awareness of researchers, journal reviewers, editors—those most in control of the distribution of information—to be cognizant of that fact that those studies in which the only source of birth defects information is the birth certificate, lacks the quality of peer-reviewed publication,” Salemi said.
Salemi JL, Tanner JP, Sampat DP, Rutkowski RE, Anjohrin SB, Marshall J, Kirby RS. Evaluation of the Sensitivity and Accuracy of Birth Defects Indicators on the 2003 Revision of the U.S. Birth Certificate: Has Data Quality Improved? Paediatric Perinatal Epidemiology. 2016 Nov 18 [Epub ahead of print]. PMID: 27859434.
Story by Anna Mayor, USF College of Public Health