Table 4.

Risk of bias assessment with the Ottawa–Newcastle scale.

Study	Selection				Comparability	Outcome			Overall	Risk of Bias
	S1	S2	S3	S4	C	O1	O2	O3
Cohort studies¥
Hirase et al., 2014[35]	0	*	*	*	0	*	0	*	5	High
Gadkaree et al., 2015[25]	*	*	*	*	**	*	*	*	9	Low
Kojima et al., 2015[26]	0	*	*	*	**	*	*	*	8	Low
Obrist et al., 2016[27]	0	*	0	*	0	0	*	0	3	High
Cleary et al., 2017[28]	0	*	0	*	0	0	*	*	4	High
Donoghue et al., 2017[29]	*	*	0	*	**	0	*	*	7	Medium
Eckstrom et al., 2017[24]	0	*	*	0	0	*	0	*	4	High
Rodriguez et al., 2017[30]	*	*	*	*	**	0	*	*	8	Low
Lai et al., 2020[32]	*	*	0	*	0	0	*	*	5	High
Yang et al., 2020[31]	0	*	0	*	**	0	*	*	6	Medium
Burns et al., 2022[33]	*	*	*	*	**	0	*	*	8	Low
Ikeda et al, 2022[34]	0	*	0	*	0	0	*	*	4	High
Cross-sectional studies¥¥
Fielding et al., 2013[16]	0	*	*	*	0	**	*	-	6	Medium
Silveira et al., 2018[17]	0	*	*	0	0	0	0	-	2	High
Chini et al., 2019[18]	*	*	*	*	0	*	*	-	6	Medium
Loonlawong et al., 2019[19]	0	*	*	*	0	*	*	-	5	High
Ferreira et al., 2021[21]	0	*	*	**	*	*	*	-	7	Low
Argyrou et al., 2022[22]	0	*	*	*	0	*	*	-	5	High
Wang et al., 2022[23]	0	*	*	*	0	*	*	-	5	High

^¥ For cohort studies: S1: representativeness of the exposed cohort; S2: selection of the non exposed cohort; S3: ascertainment of exposure; S4: demonstration that outcome of interest was not present at start of the study; O1: assessment of outcome; O2: was follow-up long enough for outcomes to occur; O3: adequacy of follow-up of cohorts.

^¥¥ For cross-sectional studies: S1: representativeness of the sample; S2: sample size, S3: non-respondents, S4: ascertainment of exposure; O1: assessment of outcome; O2: statistical test