Premature Death Rate Data

Premature death rate measures mortality by counting deaths at earlier ages more than deaths at later ages. For example, when a person dies at 20, this death contributes 55 years of potential life lost. In contrast, when a person dies at age 70, this death contributes only five years of potential life lost to a county. For our purposes, premature deaths occur before age 75. Counties with older populations are more likely to have higher crude premature death rates than counties with younger populations. Therefore, when age-adjusted, we remove the effect of differently aged populations as a risk factor for premature death. This allows us to make a fair comparison of premature death rates across counties.

过早死亡率（premature death rate）通过对早逝赋予更高权重的方式量化死亡水平：早年死亡相较于晚年死亡，将被计入更多的潜在寿命损失。举例而言，若一人于20岁时离世，该死亡案例将贡献55年的潜在寿命损失；相较之下，若一人于70岁时离世，则仅为所在县贡献5年的潜在寿命损失。就本研究的界定标准而言，过早死亡指发生于75岁之前的死亡。相较于人口结构更年轻化的县，人口老龄化程度更高的县往往会出现更高的粗过早死亡率（crude premature death rate）。因此，经年龄标准化（age-adjusted）处理后，我们可消除人口年龄结构差异作为过早死亡风险因素所带来的影响，进而能够对不同县域的过早死亡率开展公平的横向比较。