Williams Bryan L, Magsumbol Melina S
Children's Foundation Research Center at Le Bonheur Children's Medical Center, Department of Pediatrics, University of Tennessee Health Sciences Center, USA.
Pediatr Rep. 2010 Jun 18;2(1):e1. doi: 10.4081/pr.2010.e1.
Rates of infant death are one of the most common indicators of a population's overall health status. Infant mortality rates (IMRs) are used to make broad inferences about the quality of health care, effects of health policies and even environmental quality. The purpose of our study was threefold: i) to examine the characteristics of births in the area in relation to gestational age and birthweight; ii) to estimate infant mortality using variable gestational age and/or birthweight criteria for live birth, and iii) to calculate proportional mortality ratios for each cause of death using variable gestational age and/or birthweight criteria for live birth. We conducted a retrospective analysis of all Shelby County resident-linked birth and infant death certificates during the years 1999 to 2004. Descriptive test statistics were used to examine infant mortality rates in relation to specific maternal and infant risk factors. Through careful examination of 1999-2004 resident-linked birth and infant death data sets, we observed a disproportionate number of non-viable live births (≤20 weeks gestation or ≤350 grams) in Shelby County. Issuance of birth certificates to these non-viable neonates is a factor that contributes to an inflated IMR. Our study demonstrates the complexity and the appropriateness of comparing infant mortality rates in smaller geographic units, given the unique characteristics of live births in Shelby County. The disproportionate number of pre-viable infants born in Shelby County greatly obfuscates neonatal mortality and de-emphasizes the importance of post-neonatal mortality.
婴儿死亡率是衡量人口总体健康状况最常用的指标之一。婴儿死亡率（IMR）被用于对医疗保健质量、卫生政策的影响乃至环境质量进行广泛推断。我们研究的目的有三个：i）研究该地区与胎龄和出生体重相关的出生特征；ii）使用不同的胎龄和/或出生体重标准来估算活产婴儿的死亡率，以及iii）使用不同的胎龄和/或出生体重标准来计算每种死因的比例死亡率。我们对1999年至2004年间所有与谢尔比县居民相关的出生和婴儿死亡证明进行了回顾性分析。描述性检验统计数据用于研究与特定母婴风险因素相关的婴儿死亡率。通过仔细检查1999 - 2004年与居民相关的出生和婴儿死亡数据集，我们发现在谢尔比县，非存活活产（妊娠≤20周或体重≤350克）的数量不成比例。向这些无法存活的新生儿发放出生证明是导致婴儿死亡率虚高的一个因素。鉴于谢尔比县活产的独特特征，我们的研究证明了在较小地理区域比较婴儿死亡率的复杂性和适当性。谢尔比县出生的未成熟婴儿数量不成比例，极大地混淆了新生儿死亡率，并淡化了新生儿期后死亡率的重要性。
