Table 1. Quality Assessment Analysis.

Study	Selection Bias	Study Design	Confounders	Blinding	Data Collection Methods	Withdrawals and Drop-outs	Global Rating
Harøy, J et al., 201719	Strong	Strong	Strong	Strong	Strong	Moderate	Strong
Ishoi, L et al., 201621	Moderate	Strong	Strong	Moderate	Strong	Strong	Strong
Polglass, G et al., 201922	Moderate	Moderate	Strong	Strong	Strong	Moderate	Strong
Kohavi, B et al., 201823	Strong	Strong	Strong	Moderate	Strong	Moderate	Strong
Serner, A et al., 201417	Strong	Weak	Strong	Strong	Strong	Strong	Moderate

Methodological quality is rated (guidance provided) for the following areas: selection bias, study design, cofounders, blinding, data collection methods, withdrawals and dropouts, intervention integrity, and analysis.

Strong - no weak ratings given

Moderate - one weak rating

Weak - two or more weak ratings