Department of International Health, Johns Hopkins University, Baltimore, USA.
Department of Biostatistics, University of Washington, Seattle, USA.
Popul Health Metr. 2022 Jan 10;20(1):3. doi: 10.1186/s12963-021-00277-w.
The mortality pattern from birth to age five is known to vary by underlying cause of mortality, which has been documented in multiple instances. Many countries without high functioning vital registration systems could benefit from estimates of age- and cause-specific mortality to inform health programming, however, to date the causes of under-five death have only been described for broad age categories such as for neonates (0-27 days), infants (0-11 months), and children age 12-59 months.
We adapt the log quadratic model to mortality patterns for children under five to all-cause child mortality and then to age- and cause-specific mortality (U5ACSM). We apply these methods to empirical sample registration system mortality data in China from 1996 to 2015. Based on these empirical data, we simulate probabilities of mortality in the case when the true relationships between age and mortality by cause are known.
We estimate U5ACSM within 0.1-0.7 deaths per 1000 livebirths in hold out strata for life tables constructed from the China sample registration system, representing considerable improvement compared to an error of 1.2 per 1000 livebirths using a standard approach. This improved prediction error for U5ACSM is consistently demonstrated for all-cause as well as pneumonia- and injury-specific mortality. We also consistently identified cause-specific mortality patterns in simulated mortality scenarios.
The log quadratic model is a significant improvement over the standard approach for deriving U5ACSM based on both simulation and empirical results.
据了解，出生至五岁的死亡率模式因死亡的根本原因而有所不同，这在多个实例中都有记录。许多没有高功能生命登记系统的国家都可以从年龄和死因特异性死亡率估计中受益，以便为卫生规划提供信息，但迄今为止，五岁以下儿童死亡的原因仅在新生儿（0-27 天）、婴儿（0-11 个月）和 12-59 个月儿童等大年龄类别中进行了描述。
我们将对数二次模型应用于五岁以下儿童的全因儿童死亡率，然后应用于年龄和死因特异性死亡率（U5ACSM）模式。我们将这些方法应用于 1996 年至 2015 年中国实证样本登记系统死亡率数据。基于这些实证数据，我们模拟了当已知年龄和死因之间的真实关系时的死亡率概率。
我们在从中国样本登记系统构建的生命表的保留层中估计 U5ACSM 为每 1000 活产 0.1-0.7 例死亡，与使用标准方法时每 1000 活产 1.2 例死亡的误差相比，有了相当大的改进。对于全因以及肺炎和伤害特异性死亡率，这种 U5ACSM 的改进预测误差都得到了一致证明。我们还在模拟死亡率情况下一致地确定了死因特异性死亡率模式。
对数二次模型在基于模拟和实证结果推导 U5ACSM 方面是标准方法的重大改进。
