Table 2.

The study designs and MINORS appraisal scores for included studies

Study	MINORs methodological criteria												Total
	1	2	3	4	5	6	7	8	9	10	11	12
Alderman et al. [24]	2	2	0	2	0	2	2	0	2	2	1	2	17
Hoffman et al. [16]	2	2	0	2	0	2	2	0	2	2	1	2	17
Cumming et al. [12]	2	2	0	1	0	1	2	0	2	2	1	2	15
Michaelsson et al. [11]	2	2	0	2	0	2	2	0	2	2	1	2	17
Huo et al. [10]	2	2	0	2	0	2	2	0	2	2	1	2	17
Bjørnerem et al. [9]	2	2	2	2	0	2	2	0	2	2	1	2	19
Crandall et al. [15]	2	2	2	2	0	2	2	0	2	2	1	2	19

The MINORs criteria include the following items: (1) a clearly stated aim, (2) inclusion of consecutive patients, (3) prospective data collection, (4) endpoints appropriate to the aim of the study, (5) unbiased assessment of the study endpoint, (6) a follow-up period appropriate to the aims of the study, (7) less than 5% loss to follow-up, (8) prospective calculation of the sample size, (9) an adequate control group, (10) contemporary groups, (11) baseline equivalence of groups, and (12) adequate statistical analyses

The items are scored as follows: 0 (not reported), 1 (reported but inadequate), and 2 (reported and adequate)