Table 2.

Quality criteria tool used to assess the level of bias in studies selected for inclusion in the review. Adapted from [24].

Good Quality (Low Risk of Bias)	Medium Quality (Moderate Risk of Bias)	Poor Quality (High Risk of Bias)
Unbiased selection of subjects, evidence of randomisation	Bias in subject selection is acknowledged and accounted for or is unavoidable	Bias in subject selection is not acknowledge or accounted for
Appropriate data analysis	Data analysis limitations are acknowledged	Inappropriate data analysis
Scientifically sound methods	Methods are sound but may not be the most appropriate	Methods are inappropriate
Accurately described methods	Methods are comprehensible and valid even if details are lacking	Methods are unclear or incomplete
Accurate and complete reporting of results	Results are reported accurately	Results are inaccurate or incomplete