Internet-based data inclusion in a population-based European collaborative follow-up study of inflammatory bowel disease patients: Description of methods used and analysis of factors influencing response rates

Table 2 Number of CD patients per center followed-up or lost to follow-up for ePQ and ePpPFU. Centers indicated in gray had not reached the 60% response rate threshold

Center	Total number of CD patients	EPQ response (%)	EPQ response without deaths and No IBD %	Reason for non response EPQ					PpPFU response (%)	PpPFU response without No IBD %	Reason for non response PpPFU				EPQ ànd PpPFU (%)
				Not willing	Untrace-able	No IBD	Death	Not started			Not willing	Untrace- able	No IBD	Not started
Almada	13	8 (62)	67	0	4	0	1	0	8 (62)	62	0	5	0	0	8 (62)
Beer Sheeva	21	13 (62)	72	2	3	2	1	0	15 (71)	71	1	5	0	0	14 (67)
Copenhagen	58	41 (71)	85	5	2	0	10	0	52 (90)	90	6	0	0	0	47 (81)
Cremona	10	7 (70)	78	2	0	0	1	0	9 (90)	90	1	0	0	0	8 (80)
Heraklion	14	7 (50)	70	0	3	0	3	1	11 (79)	79	0	5	0	0	9 (64)
Ioannina	6	4 (67)	80	0	1	1	1	0	5 (83)	83	0	1	0	0	5 (83)
Oslo	110	69 (63)	70	15	13	0	11	1	97 (88)	89	4	8	1	0	79 (73)
Reggio Emilia	34	24 (71)	77	0	7	0	3	0	27 (79)	79	1	6	0	0	27 (79)
S-Limburg	77	60 (78)	82	8	5	0	4	0	69 (90)	90	0	8	0	0	61 (79)
Vigo	35	27 (77)	84	1	4	0	3	0	30 (86)	86	1	4	0	0	30 (86)
SUBTOTAL	378	260 (69)	77	33	42	3	38	2	323 (85)	85	14	42	1	0	288 (76)
Dublin	63	17 (27)	30	2	25	2	5	12	25 (40)	40	0	6	1	31	17 (27)
Firenze	29	13 (45)	45	0	0	0	0	16	13 (45)	45	0	1	0	15	11 (38)
Milano	13	4 (31)	50	0	2	0	5	2	0 (0)	0	0	0	0	13	0 (0)
SUBTOTAL	105	34 (32)	36	2	27	2	10	30	38 (36)	37	0	7	1	59	28 (27)
TOTAL	483	294 (61)	69	35	69	5	48	32	361 (75)	75	14	49	2	59	316 (65)