Table 1. Level of Evidence of Included RFA Studies.

Study Design	Level of Evidence†	Number of Eligible Studies
Large RCT (n> 100), systematic review of RCTs	1	1, 12
Large RCT unpublished but reported to an international scientific meeting	1(g)
Small RCT (n < 100)	2	7
Small RCT unpublished but reported to an international scientific meeting	2(g)
Non-RCT with contemporaneous controls	3a	5
Non-RCT with historical controls	3b
Non-RCT presented at international conference	3(g)
Surveillance (database or register)	4a	1
Case series (multisite)	4b	2
Case series (single site)	4c	11
Retrospective review, modelling	4d
Case series presented at international conference	4(g)

* RCT refers to randomized controlled trial;