Huang, Z., Lin, H., Liu, Y., Zhou, M., Liu, T., Xiao, J., Zeng, W., Li, X., Zhang, Y., Ebi, K.L., Tong, S., Ma, W. and Wang, L. 2015. Individual-level and community-level effect modifiers of the temperature-mortality relationship in 66 Chinese communities. BMJ Open 5: 10.1136/bmjopen-2015-009172.
Working with community-specific daily mortality data for the period 1 January 2006 to 31 December 2011 (which they obtained from the Chinese Center for Disease Control and Prevention) together with community-specific daily meteorological data for the same period (which they obtained from the China National Weather Data Sharing System), Huang et al. (2015) found that temperature-mortality relationships were "approximately V-shaped or U-shaped, with a minimum mortality temperature (MMT)," above and below which human mortality increased. And for each of the 66 communities they studied, therefore, they calculated "the change in mortality risk for a 1°C decrease in temperature below the MMT (cold effect) and for a 1°C temperature increase above the MMT (heat effect)."
This work revealed that a 1°C temperature increase above the MMT resulted in a mean increase of 1.04% in human mortality for the 66 communities, while a 1°C temperature decrease below the MMT resulted in a mean increase of 3.44% in human mortality, demonstrating that cooling below the minimum mortality temperature was 3.31 times more deadly for the residents of the 66 Chinese communities than was warming above it.Posted 16 March 2016