Table 2. MINORS score in non-randomized studies included in the review.

	He et al. 2021	Potretzke et al. 2016	Mariappan et al. 2006
A clearly stated aim	2	2	2
Inclusion of consecutive samples	2	2	2
Prospective collection of data	0	0	2
Endpoints appropriate to the aim of the study	2	2	2
Unbiased assessment of the study endpoint	0	0	0
Follow-up period appropriate to the aim of the study	2	2	2
Loss to follow-up less than 5%	2	2	2
Prospective calculation of the study size	0	0	0
An adequate control group	2	2	2
Contemporary groups	2	2	2
Baseline equivalence of groups	2	2	2
Adequate statistical analyses	2	2	2
Total	18	18	20

MINORS, methodological index for non-randomized studies. The items are scored as 0 (not reported), 1 (reported but inadequate), or 2 (reported and adequate). The global ideal score is 16 for non-comparative studies and 24 for comparative studies.