Nasejje Justine B, Mwambi Henry G, Achia Thomas N O
School of Mathematics, Statistics and Computer Science, University of KwaZulu-Natal, 22 St. Patricks road, Scottsville, Pietermaritzburg, South Africa.
Division of Epidemiology and Biostatistics, School of Public Health, University of Witwatersrand, Witwatersrand, South Africa.
BMC Public Health. 2015 Oct 1;15:1003. doi: 10.1186/s12889-015-2332-y.
Infant and child mortality rates are among the health indicators of importance in a given community or country. It is the fourth millennium development goal that by 2015, all the United Nations member countries are expected to have reduced their infant and child mortality rates by two-thirds. Uganda is one of those countries in Sub-Saharan Africa with high infant and child mortality rates, therefore it is important to use sound statistical methods to determine which factors are strongly associated with child mortality which in turn will help inform the design of intervention strategies
The Uganda Demographic Health Survey (UDHS) funded by USAID, UNFPA, UNICEF, Irish Aid and the United Kingdom government provides a data set which is rich in information on child mortality or survival. Survival analysis techniques are among the well-developed methods in Statistics for analysing time to event data. These methods were adopted in this paper to examine factors affecting under-five child mortality rates (UMR) in Uganda using the UDHS data for 2011 in R and STATA software.
Results obtained by fitting the Cox-proportional hazard model with frailty effects and drawing inference using both the frequentists and Bayesian approaches at 5 % significance level, show evidence of the existence of unobserved heterogeneity at the household level but there was not enough evidence to conclude the existence of unobserved heterogeneity at the community level. Sex of the household head, sex of the child and number of births in the past one year were found to be significant. The results further suggest that over the period of 1990-2015, Uganda reduced its UMR by 52 % .
Uganda has not achieved the MDG4 target but the 52 % reduction in the UMR is a move in the positive direction. Demographic factors (sex of the household head) and Biological determinants (sex of the child and number of births in the past one year) are strongly associated with high UMR. Heterogeneity or unobserved covariates were found to be significant at the household but insignificant at the community level.
婴幼儿死亡率是特定社区或国家重要的健康指标之一。联合国千年发展目标的第四个目标是,到2015年,所有联合国成员国应将其婴幼儿死亡率降低三分之二。乌干达是撒哈拉以南非洲地区婴幼儿死亡率较高的国家之一,因此,运用合理的统计方法来确定哪些因素与儿童死亡率密切相关,这反过来将有助于为干预策略的设计提供依据。
由美国国际开发署、联合国人口基金、联合国儿童基金会、爱尔兰援助机构和英国政府资助的乌干达人口与健康调查(UDHS)提供了一个数据集,该数据集包含丰富的儿童死亡率或存活率信息。生存分析技术是统计学中用于分析事件发生时间数据的成熟方法之一。本文采用这些方法,利用2011年乌干达人口与健康调查数据,在R和STATA软件中研究影响乌干达五岁以下儿童死亡率(UMR)的因素。
通过拟合具有脆弱效应的Cox比例风险模型,并在5%显著性水平下使用频率论和贝叶斯方法进行推断,结果表明在家庭层面存在未观察到的异质性,但没有足够证据得出在社区层面存在未观察到的异质性的结论。户主性别、孩子性别和过去一年的生育次数被发现具有显著性。结果还表明,在1990 - 20## 年期间,乌干达的五岁以下儿童死亡率降低了52%。
乌干达尚未实现千年发展目标4,但五岁以下儿童死亡率降低52%是朝着积极方向迈出的一步。人口因素(户主性别)和生物学决定因素(孩子性别和过去一年的生育次数)与高五岁以下儿童死亡率密切相关。异质性或未观察到的协变量在家庭层面具有显著性,但在社区层面不显著。