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The location of seventeen included studies (N = 11 regions). Red location mark represents the city conducted the study, including Beijing; Shaoxing of Zhejiang province; Jining of Shandong province; Guangyuan of Sichuan province; Shanghai; Shenzhen of Guangdong province; Liuyang of Hunan province; Shijiazhuang of Hebei province; Guangzhou of Guangdong province; Taiwan, and Hong Kong.
