Table 2.

Summary of ROBINS-I Risk of Bias Assessment for Included Studies

Study	Bias due to Confounding	Bias in Selection of Participants	Bias in Classification of Interventions	Bias due to Deviations from Intended Interventions	Bias due to Missing Data	Bias in Measurement of Outcomes	Bias in Selection of the Reported Result	Overall Risk of Bias
Xie Guisi [15]	Serious	Moderate	Low	Low	Low	Moderate	Moderate	Serious
Cai Zijun [16]	Serious	Moderate	Low	Low	Low	Moderate	Moderate	Serious
Zhang 17	Serious	Moderate	Low	Low	Low	Moderate	Moderate	Serious
Kang 18	Moderate	Moderate	Low	Low	Low	Moderate	Moderate	Moderate
Tang [25]	Serious	Moderate	Low	Low	Low	Moderate	Moderate	Serious
Wang [19]	Serious	Moderate	Low	Low	Low	Moderate	Moderate	Serious
Kim [20]	Serious	Moderate	Low	Low	Low	Moderate	Moderate	Serious
Zhong [24}	Serious	Moderate	Low	Low	Low	Moderate	Moderate	Serious
Zhao [21]	Serious	Moderate	Low	Low	Moderate	Moderate	Moderate	Serious
Yu [22]	Serious	Moderate	Low	Low	Low	Moderate	Moderate	Serious
Yan [23]	Serious	Moderate	Low	Low	Low	Moderate	Moderate	Serious
Huang Pengbo [26]	Serious	Moderate	Low	Low	Low	Moderate	Moderate	Serious