Validation of the VEINES-QOL quality of life instrument in venous leg ulcers: repeatability and validity study embedded in a randomised clinical trial

Table 7 Intraclass correlation coefficients, within subject standard deviation, and repeatability coefficient for 2-week test-retest reliability for VEINES-QOL and VEINES-Sym

Scale and scoring	ICC^a	SE	95 % CI	Within-subject SD	Repeatability coefficient^b
VEINES-QOL
Original	0.80	0.019	0.76–0.83	4.5	12.5
External standard	0.79	0.019	0.75–0.83	4.6	12.8
Intrinsic	0.78	0.020	0.74–0.82	10.6	29.4
VEINES-Sym
Original	0.75	0.022	0.71–0.79	5.0	13.8
External standard	0.75	0.022	0.71–0.79	5.1	14.1
Intrinsic	0.74	0.023	0.69–0.79	11.9	33.0

^aICC = intraclass correlation coefficient, which lies between 0 and 1.0. For acceptable repeatability this should be greater than 0.070
^b95 % of pairs of replicate measurements on the same person will be less than this, so a larger difference would indicate a change in quality of life

ISSN: 1471-2261