. 2019 Feb 4;9:1159. doi: 10.1038/s41598-018-37617-0

Table 2.

Risk of bias for included studies.

ROBINS-I	Kooby¹⁸	Magge²⁶	Rehman¹⁶	Sharpe³⁶	Shin³⁷	Sulpice⁴⁰	Zhang¹⁷	Stauffer¹⁹	Bauman⁴⁴	Hilst¹²	Zhang⁵⁶
Bias due to confounding	L	L	S	S	L	M	L	S	S	L	S
Bias in selection of participants into the study	M	L	L	L	L	L	L	L	L	L	L
Bias in measurement of interventions	L	L	L	L	L	M	L	L	L	L	L
Bias due to departures from intended interventions	M	M	M	L	L	M	M	M	M	L	M
Bias due to missing data	L	L	L	L	L	L	L	L	L	L	L
Bias in measurement of outcomes	L	L	L	L	L	L	L	L	M	L	L
Bias in selection of the reported result	L	M	M	M	L	M	M	M	M	L	M
Overall	M	M	S	S	L	M	M	S	S	L	S

ROBINS-I = Risk of bias in non-randomized studies of interventions; L = Lower; M = Moderate; S = Serious.