Table 3

Quality assessment of studies based on Effective Public Health Practice Project criteria: total score and quality according to global and component ratings*

Source, country	Total score (4–18)	Global rating	Selection bias	Study design	Control of confounders	Blinding	Data collection methods	Withdrawals and drop-outs
Autret et al (2015), France	9	Weak	Weak	Moderate	Weak	N/A	Moderate	Strong
Bonner et al (2016), India	8	Moderate	Moderate	Weak	Strong	N/A	Moderate	N/A
Bonneterre et al (2013), France	9	Weak	Weak	Moderate	Moderate	N/A	Weak	Strong
de Koning et al (2017), The Netherlands	12	Strong	Moderate	Moderate	Strong	N/A	Strong	Moderate
Endo et al (2016), Japan	14	Strong	Strong	Moderate	Strong	N/A	Strong	Strong
Hannerz et al (2011), Denmark	12	Moderate	Strong	Moderate	Weak	N/A	Strong	Strong
Hannerz et al (2012), Denmark	14	Strong	Strong	Moderate	Strong	N/A	Strong	Strong
Johnson (1987), Great Britain	11	Moderate	Weak	Moderate	Moderate	N/A	Strong	Strong
Ntsiea et al (2015), South Africa	14	Moderate	Moderate	Strong	Weak	Moderate	Strong	Strong
Saeki et al (1995), Japan	7	Weak	Moderate	Moderate	Weak	N/A	Weak	Weak
van Dongen et al (2018), The Netherlands	9	Weak	Weak	Moderate	Weak	N/A	Moderate	Strong
Vestling et al (2003), Sweden	10	Moderate	Moderate	Moderate	Strong	N/A	Moderate	Weak
Walker et al (2006), USA	12	Strong	Moderate	Moderate	Strong	N/A	Strong	Moderate

*Total score computed by converting strong=3, moderate=2, weak=1 and N/A=0, and computing a sum score. Global rating was assigned according to the EPHPP guidelines (strong=no weak ratings, moderate=one weak rating, weak=two or more weak ratings).
N/A, not applicable.