TABLE 2.

Summary of Methodologic Quality Ratings by Study

Source	Global Rating	Selection Bias	Study Design	Confounders	Blinding	Data Collection Method	Withdrawals and Dropouts
Costa et al27	Weak	Weak	Moderate	Weak	Moderate	Strong	Weak
de Vries et al28	Weak	Weak	Moderate	Weak	Moderate	Strong	Weak
de Vries et al29	Weak	Weak	Moderate	Weak	Moderate	Strong	Weak
Diamond et al30	Weak	Weak	Moderate	Weak	Moderate	Strong	Strong
Lucassen et al31	Weak	Weak	Moderate	Weak	Moderate	Strong	Strong
Raifman et al33	Strong	Moderate	Moderate	Strong	Strong	Strong	Moderate
Painter et al32	Weak	Weak	Moderate	Weak	Moderate	Strong	Weak
Schwinn et al34	Weak	Weak	Strong	Weak	Moderate	Weak	Strong
Seelman and Walker35	Moderate	Moderate	Moderate	Weak	Strong	Strong	Moderate

Methodologic assessments were determined according to the Quality Assessment Tool for Quantitative Studies checklist.