TABLE 3.

Quality assessment of the individual study, based on a modified version of the NOS

	Selection				Outcome		Total stars
	1	2	3	4	5	6
	Clear description sample	Representativeness sample	Sample size	Non responders	Clear variables	Outcome assessment
Aminaie	2	0	0	0	2	2	6
Atherton	2	1	1	0	2	2	8
Berger	2	1	0	0	2	2	7
Bieber	2	0	0	0	2	2	6
Brown	2	0	0	0	2	2	6
Burton	2	0	0	0	2	2	6
Carey	1	1	0	0	2	2	6
Engelhardt	2	0	1	0	2	1	6
Ghoshal	1	0	1	0	1	2	5
Hamelinck	2	0	0	0	2	2	6
Herrmann	2	0	0	1	2	2	7
Hitz	2	1	1	0	2	2	8
Hotta	1	0	0	0	2	2	5
Hou	1	0	0	0	1	2	4
Kehl	2	1	0	0	2	2	7
Mack	1	0	1	0	2	2	6
Mansfield	1	0	1	1	2	2	7
Moth 2016	2	1	0	0	2	2	7
Moth 2019	2	1	0	0	2	2	7
Nakashima	2	0	0	0	2	2	6
Nguyen	2	0	0	0	1	1	4
Nicolai	2	0	0	0	2	2	6
Nies	2	1	0	0	2	2	7
Palmer	2	1	0	0	2	2	7
Sepucha	2	0	0	0	2	2	6
Seror	2	1	0	0	2	2	7
Stacey	1	0	0	0	2	2	5
van Stam	2	1	0	1	2	2	8
Wang	2	0	0	0	2	1	5
Yamauchi	2	0	0	0	2	2	6
Yogaparan	1	0	0	0	2	2	5

Note: Number of stars for ‘selection of participants’ and ‘definition and assessment of the outcome’. Maximum number of stars for selection = 5; Maximum number of stars for outcome = 4. Number of stars 0–3: poor quality, 4–6: fair quality, 7–9: good quality (note that this is based on an adapted scoring from the NOS).

Abbreviation: NOS, Newcastle‐Ottawa scale.