Table 3.

Risk of bias using MINORS tool for retrospective studies [35]

MINORS tool	Rapidis 1985	Shen 2013	Boffano 2014	Kale 2015
1. A clearly stated aim	0	2	2	2
2. Inclusion of consecutive patients	2	2	2	2
3. Prospective collection of data	1	2	2	2
4. Endpoints appropriate to the aim of the study	0	2	1	2
5. Unbiased assessment of the study endpoint	0	1	1	1
6. Follow-up period appropriate to the aim of the study	0	2	0	2
7. Loss to follow up less than 5%	0	2	0	2
8. Prospective calculation of the study size	0	0	0	0
Total	3/16	13/16	8/16	13/16

0 = not reported 1 = reported but not adequate 2 = reported and adequate