Table 2.

Study designs and evidence levels.

Study design	Oxford evidence level	GRADE evidence level	Articles
Phase 2 clinical trial: multicenter, double-blind, randomized, controlled	1a	high	19,27
Clinical trial: single-center, randomized, double-blind, controlled	1b	moderate	31
Phase 1 clinical trial: multicenter, open-label, randomized, controlled	1b	moderate	33
Phase 1 clinical trial: single-center, double-blinded, randomized, controlled	1b	moderate	14
Phase 1 clinical trial: multicenter, open-label, non-randomized, noncontrolled	2b	low	26,38
Pilot trial: single-center, open-label, non-randomized, controlled	2b	low	34
Phase 1 clinical trial: single-center, open-label, non-randomized, controlled	2b	low	17
Clinical trial: multicenter, open-label, non-randomized, noncontrolled	2b	low	32
Clinical trial: single-center
open-label, randomized, controlled	2b	low	18
Pilot trial: multicenter, open-label, non-randomized, noncontrolled	2b	low	21,36
Clinical trial: single-center, open-label, non-randomized, noncontrolled	2c	low	11,22,23,28,29
Pilot trial: single-center, open-label, non-randomized, noncontrolled	2c	low	16
Cohort	4c	very low	24
Case report	4c	very low	13,20,24,30,35,37,63
Case series	4c	very low	25