Table 4.

Assessment of risk of bias for cross-sectional studies according to the Joanna Briggs Institute (JBI) checklist

Study authors	Q1	Q2	Q3	Q4	Q5	Q6	Q7	Q8	Overall risk of bias assessment
Lisicki M et al. [44]	Yes	Yes	No	Yes	No	Yes	Yes	Yes	Moderate
Aamodt AH et al. [46]	Yes	Yes	No	Yes	No	No	Yes	Yes	High
Lebedeva ER et al. [27]	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Low
Misakian AL et al. [47]	Yes	Yes	No	Yes	No	No	Yes	Yes	High
Le H et al. [51]	No	Unclear	No	Yes	Yes	Yes	Yes	Yes	High
Kaltseis K et al. [26]	Yes	Yes	Yes	Yes	Yes	Unclear	Yes	Yes	Low
Pellegrino Baena C et al. [56]	Yes	Yes	No	Yes	Unclear	No	Yes	Yes	High
McMurtray AM et al. [57]	Yes	Yes	No	Yes	Yes	No	Yes	Yes	Moderate
Rasmussen BK [60]	Yes	Yes	No	Yes	No	No	Yes	Yes	High
Scher AI et al. [71]	Yes	Yes	No	Yes	Yes	No	Yes	Yes	Moderate
Luo J [48]	Yes	Yes	No	No	Yes	Unclear	Yes	Yes	High

Q1—Were the criteria for inclusion in the sample clearly defined?

Q2—Were the study subjects and the setting described in detail?

Q3—Was the exposure measured in a valid and reliable way?

Q4—Were objective, standard criteria used for measurement of the condition?

Q5—Were confounding factors identified?

Q6—Were strategies to deal with confounding factors stated?

Q7—Were the outcomes measured in a valid and reliable way?

Q8—Was appropriate statistical analysis used?