Table 1. Characteristics of included studies.

Authors and year of publication	Outcomes investigated	Published journal	Location and period of data obtained	Study design	Model	No. events	Variables controlled	Lags (single/average/both)
Ma et al., 2011	CHD mortality	European Heart Journal	China, Shanghai,2006–2008	Time-series	Over-dispersed generalized linear Poisson models	22,272	Long-term and seasonal trends,temperature, relative humidity, PM10, and O3 concentrations	Both
Yap et al., 2016	Overall mortality, cardiovascular mortality, incident MI, stroke, HF	International Journal of Cardiology	Singapore,2001–2012	Time-series	Generalized linear model	Na	Air pollutant levels	NA
Zhang et al., 2013	Stroke deaths	Journal of Cardiovascular Medicine	Nine urban districts of Shanghai,2006–2008	Time-series	Generalized linear model	29,566	Air pollutant levels, day of the week, temperature, humidity	Both
Lin et al., 2013	Cardiovascular mortality	PLoS One	Taishan and Guangzhou, 2006–2010	Time-series	Generalized linear model and distributed lag non-linear model	41,085	Public holidays, day of the week, temperature, humidity, air pollutant levels	Both