Table 2. Anatomic and vascular characteristics of the study population in general and stratified by AVF maturation status (n = 145).

	Total Population n = 145 (100%)		Mature AVF n = 113 (77.9%)		Immature AVF n = 32 (22.1%)		p-value
	Total or median	% or IQR	Total or median	% or IQR	Total or median	% or IQR
Arm circumference, cm	28	26/32	28	25/30	31.5	28/36	0.001
Skinfold thickness, cm	2.2	1.5/3.0	1.9	1.3/2.8	2.7	2.2/3.6	0.001
Skinfold thickness, cm	2.2	1.5/3.0	1.9	1.3/2.8	2.7	2.2/3.6	0.001
Vein pre-AVF, cm	0.4	0.3/0.4	0.4	0.3/0.4	0.3	0.3/0.4	0.093
Artery pre-AVF, cm	0.4	0.3/0.5	0.4	0.3/0.5	0.3	0.2/0.4	0.001
Side							0.873
Right	47	32.4	37	32.7	10	31.2
Left	98	67.6	76	67.3	22	68.7
Height							<0.001
Arm	93	64.1	81	71.7	12	37.5
Forearm	52	35.9	32	28.3	20	62.5
AVF							0.033
Brachiocephalic	67	46.2	57	50.4	10	31.2
Radiocephalic	53	36.5	34	30.1	19	59.4
Brachiobasilic	18	12.4	16	14.2	2	6.2
Brachio-perforating	4	2.8	4	3.5	0	0
Brachio-brachial	3	2.1	2	1.8	1	3.1

IQR = interquartile range (25^th percentile/75^th percentile); AVF = arteriovenous fistula.