Table 2 List of main studies compared between one-stage and two-stage procedures in TBB­AVF.

Authors	Year	Study type	Number	Maturation rate (%)		Secondary patency at 2 years		Complication	Recommendation
				One stage	Two stage	One stage	Two stage
El Mallah	1998	Randomized	One stage 20	60	90				Two stage
			Two stage 20
Hossny	2003	Retrospective	One-stage transposition 40			Transposition 82.8	Elevation 68.4	Hematoma: 26.3% in elevation group
			One-stage elevation 20			Elevation 70
			Two-stage elevation 20
Kakkos	2010	Retrospective	One-stage transposition 76	85**	82**			Complications: higher in one-stage method	Two stage
			Two-stage transposition 98 (72)*					10 in two-stage group did not attain second stage
Reynolds	2011	Retrospective	One-stage transposition 60	77.1	90.9	41	94	30 days complications: similar in both groups	Two stage
			Two-stage tansposition 30
Syed	2012	Retrospective		79	82	81	27
Vrakas	2013	Retrospective	One-stage transposition 65	55	58	57	77	Complications: similar in both groups	Two stage
			Two-stage elevation 84
Ozcan	2013	Retrospective	One stage 47 (basilic vein >3 mm)	66	77	98	98	Complications: higher in one-stage method	Two stage
			Two stage 59 (basilic vein <3 mm)
Robertson	2013	Retrospective	One stage 29	76	84	86.2***	91.6***		One stage
			Two stage 44
Agarwal	2014	Retrospective	One stage 61	90	75	75	71	Required interventions: similar in both groups
			Two stage 83
Kakkos	2015	Randomized	One-stage transposition 9	33	100	44	86		Two stage
			Two-stage transposition 7
Ghaffarian	2017	Retrospective	One stage 57			44	73	Complications: similar in both groups	Two stage
			Two stage 74					Two stage was durable and cost-effective

*: 72 out of 98 underwent a second-stage operation; **: including lost or refuse patients; ***: secondary patency at 6 months