Factors affecting maternal participation in the genetic component of the National Birth Defects Prevention Study-United States, 1997-2007.
OBJECTIVE
As epidemiological studies expand to examine gene-environment interaction effects, it is important to identify factors associated with participation in genetic studies. The National Birth Defects Prevention Study is a multisite case-control study designed to investigate environmental and genetic risk factors for major birth defects. The National Birth Defects Prevention Study includes maternal telephone interviews and mailed buccal cell self-collection kits. Because subjects can participate in the interview, independent of buccal cell collection, detailed analysis of factors associated with participation in buccal cell collection was possible.


METHODS
Multivariable logistic regression models were used to identify the factors associated with participation in the genetic component of the study.


RESULTS
Buccal cell participation rates varied by race/ethnicity (non-Hispanic whites, 66.9%; Hispanics, 60.4%; and non-Hispanic blacks, 47.3%) and study site (50.2-74.2%). Additional monetary incentive following return of buccal cell kit and shorter interval between infant's estimated date of delivery and interview were associated with increased participation across all racial/ethnic groups. Higher education and delivering an infant with a birth defect were associated with increased participation among non-Hispanic whites and Hispanics.


CONCLUSIONS
Factors associated with participation varied by race/ethnicity. Improved understanding of factors associated with participation may facilitate strategies to increase participation, thereby improving generalizability of study findings.
1] National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia, USA [2] Epidemic Intelligence Service, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
Jill
J
Glidewell
National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
Jennita
J
Reefhuis
National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
Sonja A
SA
Rasmussen
Department of Epidemiology, University of North Carolina Gillings School of Global Public Health, Chapel Hill, North Carolina, USA.
Alison
A
Woomert
Department of Pediatrics, University of Arkansas for Medical Sciences College of Medicine, Little Rock, Arkansas, USA.
Charlotte
C
Hobbs
Department of Epidemiology, University of Iowa College of Public Health, Iowa City, Iowa, USA.
Paul A
PA
Romitti
National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
Krista S
KS
Crider
D001294:Attitude to Health / Q000208:ethnology*; D016022:Case-Control Studies; D000013:Congenital Abnormalities / Q000235:genetics* / Q000517:prevention & control; D005260:Female; D006801:Humans; D007407:Interviews as Topic; D016015:Logistic Models; D009061:Mouth Mucosa / Q000166:cytology*; D010358:Patient Participation; D012307:Risk Factors