Daily exceedance concentration hours: A novel indicator to measure acute cardiovascular effects of PM2.5 in six Chinese subtropical cities
Keywords: طبقه بندی بین المللی بیماری ها; DECH; daily exceedance concentration hours; PM2.5; airborne particulate matter smaller than 2.5 μm; CI; confidence interval; PRD; Pearl River Delta; ICD; International Classification of Diseases; CVD; cardiovascular diseases; IHD; ischemic heart disease