Table 1.

Critical appraisal results

Study	Selection bias	Study design	Confounders	Blinding	Data collection method	Withdrawals and dropouts	Global rating
Aboalshamat et al. (2020)	Moderate	Moderate	Strong	Weak	Strong	Strong	Moderate
Adams (2017)	Weak	Weak	Weak	Weak	Strong	Weak	Weak
Brake et al. (2001) Gorter et al. (2001)	Weak	Moderate	Weak	Weak	Strong	Strong	Weak
Chapman et al. (2017)	Weak	Moderate	Strong	Weak	Strong	Moderate	Weak
Gonzalez & Quezada (2016)	Weak	Weak	Weak	Weak	Strong	Strong	Weak
Metz et al. (2020)	Strong	Moderate	Strong	Weak	Strong	Strong	Moderate
Newton et al. (2006)	Weak	Moderate	Weak	Weak	Strong	Weak	Weak
Piazza-Waggoner et al. (2003)	Strong	Moderate	Weak	Weak	Strong	Weak	Weak