Table 2.

MINORS quality assessment

Study	Clearly stated aim	Inclusion consecutive patients	Prospective data collection	Appropriate endpoints to the aim	Unbiased Study endpoint	Appropriate follow-up period	Loss to follow-up < 5%	Prospective calculation of study size	Adequate control group	Contemporary groups	Baseline equivalence of groups	Adequate statistical analysis	Total quality score
Jiang et al. [11]	1	N/a	0	2	0	2	N/a	N/a	N/a	N/a	N/a	N/a	5 / 16
Klei et al. [24]	2	2	0	2	0	2	2	0	2	2	1	2	17 / 24
Krinner et al. [3]	1	0	0	1	0	2	2	0	N/a	N/a	N/a	N/a	6 / 16
Labbe et al. [10]	1	0	0	2	0	0	0	0	N/a	N/a	N/a	N/a	3 / 16
Regauer et al. [26]	1	N/a	0	2	0	2	N/a	N/a	N/a	N/a	N/a	N/a	5 / 16
Sarkeshik et al. [33]	1	N/a	0	1	0	2	N/a	N/a	N/a	N/a	N/a	N/a	4 / 16

MINORS criteria: 0 = not reported, 1 = reported but inadequate, 2 = reported and adequate. N/a, not applicable

For case reports and case series, the eight criteria for non-comparative studies were used (maximum total score of 16 points). For the retrospective cohort study, four criteria for comperative studies were added (maximum total score of 24 points)