Show simple item record

dc.contributor.advisorRich-Edwards, Janet W.
dc.contributor.authorHeinke, Dominique
dc.date.accessioned2018-12-20T13:37:00Z
dash.embargo.terms2019-05-01
dc.date.created2018-05
dc.date.issued2018-04-27
dc.date.submitted2018
dc.identifier.urihttp://nrs.harvard.edu/urn-3:HUL.InstRepos:37945561*
dc.description.abstractGlobally, each year over 4 million infants die during the perinatal period, which includes stillbirth and neonatal death, yet little investment has been made in research or preventative efforts. Birth defects are common among perinatal deaths: major birth defects are identified among 15 to 20% of stillbirths and 20% infant deaths. Due to the interconnections between perinatal outcomes, studies of both perinatal deaths and of risk factors for birth defects may be biased by the occurrence of competing events which may deplete the susceptible population at risk, alter the category of a death without changing the risk of mortality, or may lead to biased risk factor assessments when analyses are conducted among survivors. We therefore sought to evaluate the impact of competing risks in studies of perinatal mortality and birth defects. First, we described the timing and etiology of stillbirths and neonatal deaths in the US during 2014. Then we examined the risk of stillbirth among fetuses with major birth defects and evaluated the effect of termination for pregnancy as a competing risk on observed stillbirth risk estimates. Finally, we evaluated whether risk factor studies of birth defects are biased when conducted among live births only. We found that the risk of stillbirth and first day mortality were higher than late neonatal deaths at all gestational ages and that stillbirth and first day deaths share have a greater etiological overlap than first day deaths and later neonatal deaths. Fetuses with major birth defects were found to have high risks of stillbirth, and that termination of pregnancy may lead to underestimates of stillbirth risk by depleting the susceptible population at risk. Risk factor studies of birth defects conducted only among live births were not found to be meaningfully biased in most situations, but studies of high mortality defects where the exposure is also very strongly associated with termination of pregnancy and stillbirth may lead to biased results. In studies of perinatal mortality and birth defects, competing risks may act to induce bias under certain circumstances.
dc.format.mimetypeapplication/pdf
dc.language.isoen
dash.licenseLAA
dc.subjectHealth Sciences, Epidemiology
dc.subjectHealth Sciences, Obstetrics and Gynecology
dc.subjectHealth Sciences, Public Health
dc.titleAn Evaluation of Competing Risks in Studies of Perinatal Mortality and Birth Defects
dc.typeThesis or Dissertation
dash.depositing.authorHeinke, Dominique
dash.embargo.until2019-05-01
dc.date.available2018-12-20T13:37:00Z
thesis.degree.date2018
thesis.degree.grantorHarvard T.H. Chan School of Public Health
thesis.degree.levelDoctoral
thesis.degree.nameDoctor of Science (SD)
dc.contributor.committeeMemberWilliams, Paige L.
dc.contributor.committeeMemberHernandez-Diaz, Sonia
dc.type.materialtext
thesis.degree.departmentEpidemiology
dash.identifier.vireohttp://etds.lib.harvard.edu/hsph/admin/view/281
dc.description.keywordsbirth defects; congenital anomalies; stillbirth; neonatal death; neonatal mortality; perinatal death; perinatal mortality; competing risks; termination of pregnancy; first day death; selection bias; cause of death; infant death; depletion of succeptibles;
dc.identifier.orcid0000-0001-9217-3723
dash.author.emaildnheinke@gmail.com


Files in this item

Thumbnail
Thumbnail

This item appears in the following Collection(s)

Show simple item record