Table 3. Risk of Bias Assessment for Non-randomized Studies (RoBANS).

First author	Selection of participants	Confounding variables	Measurement of exposure	Blinding of outcome assessments	Incomplete outcome data	Selective outcome reporting
2021, Kitamura	High	High	Low	Unclear	Low	Low
2018, Harada	Low	Low	Low	Unclear	Low	Low
2016, Miura	High	High	Low	Unclear	Low	Low
2017, Kanamori	High	High	Low	Unclear	Low	Low
2018, Yoshida	High	High	Low	Unclear	Low	Low
2019, Takezawa	High	High	Low	Unclear	Low	Low