Table 2.

The Joanna Briggs Institute critical appraisal checklist

Study	Were the criteria for inclusion in the sample clearly defined?	Were the study subjects and the setting described in detail?	Was the exposure measured in a valid and reliable way?	Were objective, standard criteria used for measurement of the condition?	Were confounding factors identified?	Were strategies to deal with confounding factors stated?	Were the outcomes measured in a valid and reliable way?	Was appropriate statistical analysis used?	Risk of bias
Andersson A	Yes	Yes	Yes	Yes	No	No	Yes	No	Low
Kai S	Yes	Yes	Yes	Yes	No	No	Yes	No	Low
Seemungal TAR	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Low
Abdallah GM	Yes	Yes	Yes	Yes	No	No	Yes	No	Low
Fimognari FL	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Low
Kahn NA	Yes	Yes	Yes	Yes	No	No	Yes	No	Low
Moayyedkazemi A	Yes	Yes	Yes	Yes	No	No	Yes	No	Low
Wei B	Yes	Yes	Yes	Yes	No	No	Yes	No	Low
Zinellu A	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Low