Table 2 Study designs and evidence levels.

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