The temperature–mortality relationship: an analysis from 31 Chinese provincial capital cities

We aim to explore the Minimum Mortality Temperature (MMT) of different cities and regions, and that provides evidence for developing reasonable heat wave definition in China. The death data of 31 Chinese provincial capital cities from seven geographical regions during 2008–2013 was included in this study. In the first stage, a DLNM (Distributed Lag Non-linear Model) was used to estimate the association between mean temperature and mortality in a single city, then we pooled them with a multivariate meta-analysis to estimate the region-specific effects. The range of MMT was from 17.4 °C (Shijiazhuang) to 28.4 °C (Haikou), and the regional MMT increased as the original latitude decreased. Different cities and regions have their own specialized MMT due to geography and demographic characteristics. These findings indicate that the government deserves to adjust measures to local conditions to develop public health policies.