title: A comparison of perinatal mortality in Korea on holidays and working days.
abstract: OBJECTIVE
  To examine whether the perinatal mortality of infants born during holidays differs from that of infants born on workdays, and to elucidate its cause.
  
  
  METHODS
  Cross-sectional study. Setting Vital statistics linked to the National Infant Mortality Survey data for 1999 births in Korea.
  
  
  METHODS
  In all, 628 485 births in 1999 in Korea.
  
  
  METHODS
  Number of births and perinatal mortality were classified according to the day of the week using the occurrence index. After adjusting for confounding factors, the odds ratios (ORs) for increased holiday mortality were estimated using logistic regression.
  
  
  METHODS
  Birthweight-adjusted perinatal mortality.
  
  
  RESULTS
  Births on holidays were 33% fewer and perinatal deaths 24% higher than expected (PMR, Perinatal Mortality Rate, 16.4 versus 12.8; OR, 1.3; 95% CI, 1.2-1.4). After the adjustment of birthweight, gender, plurality and congenital anomalies, the odds ratio for death of infants born during holidays was 1.2 (95% CI, 1.1-1.3).
  
  
  CONCLUSIONS
  The higher perinatal mortality during holidays in Korea appears to be due to different qualities of perinatal care, rather than difference in case-mix.
authors.affiliation: Graduate School of Public Health, Yonsei University, Seoul, Korea.
authors.forename: J S
authors.initials: JS
authors.lastname: Hong
authors.forename: H C
authors.initials: HC
authors.lastname: Kang
authors.forename: S-W
authors.initials: SW
authors.lastname: Yi
authors.forename: Y J
authors.initials: YJ
authors.lastname: Han
authors.forename: C M
authors.initials: CM
authors.lastname: Nam
authors.forename: B
authors.initials: B
authors.lastname: Gombojav
authors.forename: H
authors.initials: H
authors.lastname: Ohrr
mesh_terms: D039602:After-Hours Care / Q000592:standards; D001724:Birth Weight / Q000502:physiology*; D003430:Cross-Sectional Studies; D003695:Delivery of Health Care / Q000592:standards; D006693:Holidays / Q000706:statistics & numerical data*; D006801:Humans; D007223:Infant; D007226:Infant Mortality; D007231:Infant, Newborn; D007723:Korea / Q000453:epidemiology; D016017:Odds Ratio; D018743:Perinatal Care / Q000592:standards*; D011787:Quality of Health Care; D012044:Regression Analysis