An evaluation of the response category translations of the EORTC QLQ-C30 questionnaire.
OBJECTIVE
The aim of this study was to evaluate the translated response categories used in eight translations of the European Organisation for Research and Treatment of Cancer QLQ-C30 questionnaire, which is used in many international clinical trials. Twenty-eight of the 30 items in the questionnaire have the same four response categories: "Not at all", "A little", "Quite a bit" and "Very Much".


METHODS
People with knowledge of both English and one of eight European languages were asked to complete an Internet survey. The strength (intensity) of the translated categories was assessed using two separate approaches: one using a verbal response scale and the other a visual analogue scale (VAS).


RESULTS
Two hundred and seventy-nine people participated in the survey. Most translations were rated similarly to English. The largest differences were for the German translation of "Quite a bit", which was rated 16.3 points lower than the corresponding English category on a 0-100 VAS.


CONCLUSIONS
Most of the translated categories were found to be similar to the English versions and should continue to be used. We recommend that three translated categories should be considered for revision. Similar surveys could be used to assess the categories used in other translated quality of life instruments.
Medical Statistics Team, Division of Applied Health Sciences, University of Aberdeen, Polwarth Building, Foresterhill, Aberdeen, AB25 2ZD, UK. n.w.scott@abdn.ac.uk
Neil W
NW
Scott
Josephine A
JA
Etta
Neil K
NK
Aaronson
Andrew
A
Bottomley
Peter M
PM
Fayers
Mogens
M
Groenvold
Michael
M
Koller
Dagmara
D
Kuliś
Debbi
D
Marais
Morten A
MA
Petersen
Mirjam A G
MA
Sprangers
D000328:Adult; D003625:Data Collection; D005060:Europe; D005260:Female; D006801:Humans; D020407:Internet; D007802:Language; D008297:Male; D009369:Neoplasms / Q000523:psychology*; D010147:Pain Measurement / Q000295:instrumentation*; D011788:Quality of Life; D011795:Surveys and Questionnaires; D014175:Translating; D014177:Translations