Table 2.

Risk of bias assessment for included RCTs

Study	Randomization process	Deviations from intended intervention	Missing outcome data	Measurement of the outcome	Selection of reported results	Overall
Fichter et al. [28]	Some concerns	Some concerns	Low risk	Low risk	Low risk	Some concerns
Kaye et al. [25]	Low risk	Low risk	Low risk	Low risk	Some concerns	Some concerns
Neumayr et al. [23]	Some concerns	Some concerns	Low risk	Low risk	Some concerns	Some concerns
Parling et al. [29]	Low risk	Some concerns	High risk	High risk	Some concerns	High risk
Pike et al. [30]	Low risk	Some concerns	Low risk	Low risk	Low risk	Some concerns
Sternheim et al. [26]	Low risk	Low risk	Low risk	Some concerns	Low risk	Some concerns
Walsh et al. [24]	Low risk	Low risk	Low risk	Some concerns	Low risk	Some concerns