Table 2.

Risk of Bias Assessments using the RoB 2 tool or the ROBINS-I tool.

Risk of Bias in Non-randomized Studies of Interventions (ROBINS-I)
Study Name	Domain 1: Risk of bias due to confounding	Domain 2: Risk of bias in selection of participants into the study	Domain 3: Risk of bias in classification of interventions	Domain 4: Risk of bias due to deviations from intended interventions	Domain 5: Risk of bias due to missing data	Domain 6: Risk of bias in measurement of outcomes	Domain 7: Risk of bias in selection of the reported result	Overall risk of bias
Ford et al. (2019)	Low	N/A	N/A	N/A	Low	Low	Low	Low
Hussar et al. (1971)	Serious	Low	Low	Low	Low	Low	Low	Serious
Friedman et al. (1967)	Moderate	Low	Low	Low	Low	Low	Low	Moderate
(Solomon et al., 1968)	Moderate	Low	Low	Low	Low	Low	Low	Moderate
Wang et al. (2016)	Moderate	N/A	N/A	N/A	Low	Low	Low	Moderate
Vaughan et al. (1949)	Moderate	Low	Low	Low	Low	Low	Low	Moderate
Armstrong-Esther et al. (1978)	Low	Low	Low	Low	Low	Low	Low	Low
Taylor et al. (2017)	Low	Low	Low	Low	Moderate	Low	Low	Low
Dopp et al. (2007)	Moderate	Low	Low	Low	Low	Low	Low	Low
Kosor Krnic et al. (2007)	Moderate	Low	Low	Low	Low	Low	Low	Low
Risk of Bias 2 (RoB 2)
	Domain 1: Risk of bias arising from the randomization process	Domain 2: Risk of bias due to deviations from the intended intervention (effect of assignment to intervention)	Domain 3: Risk of bias due to missing outcome data	Domain 4: Risk of bias in measurement of the outcome	Domain 5: Risk of bias in selection of the reported result	Overall risk of bias
Cassiers et al. (2019)	Low	Low	Low	Low	Low	Low
Niemegeers et al. (2016)	Low	Low	Low	Low	Low	Low

Note: N/A refers to domains that were not applicable for that study.