Table 2. Individual studies risk of bias on effect of ANC on perinatal outcomes in Ethiopia.

Studies	Selection bias	Attrition bias	Performance bias	Detection bias	Confounding bias	Reporting bias
Adane et al. 2014	Low	Low	Low	High	Low	Low
Ballard et al. 2016	Low	Low	Low	High	High	Low
Berhan 2014	Low	Low	Unclear	High	High	Low
Berhie and Gebresilassie 2016	Low	Low	Low	High	Low	Low
Eyob and Worku 2003	Low	Low	Unclear	High	High	Low
Getiye and Fantahun 2017	Low	Low	Low	High	Low	Low
Goba et al. 2017	Low	Low	Unclear	High	Low	Low
Lakew et al. 2017	Low	Low	Low	High	Low	Low
Roro et al. 2018	Low	Unclear	Low	High	Low	Low
Tilahun & Assefa 2017	Low	Low	Low	High	Low	Low
Tilahun and Gaym 2008	Low	Unclear	Low	High	Low	Low
Welegebriel et al. 2017	Low	Unclear	Low	High	Low	Low
Worede and Dagnew 2019	Low	Low	Low	High	Low	Low
Worku et al. 2013	Low	Low	Low	High	Unclear	Low
Chekol A., 2011	Low	Low	Low	High	Low	Low
Aragaw Y., 2016	Low	Low	Low	High	Low	Unclear
Mihiretu A. et al, 2017	Low	Low	Low	High	Low	Unclear