J Clin Epidemiol Vol. 51, No. 11, pp. 925–932, 1998
Copyright © 1998 Elsevier Science Inc. All rights reserved.
0895-4356/98 $–see front matter
PII S0895-4356(98)00083-3
Cross-Cultural Comparisons of the Content of SF-36
Translations across 10 Countries: Results from the
IQOLA Project
Anita K. Wagner,
1
* Barbara Gandek,
1
Neil K. Aaronson,
2
Catherine Acquadro,
3
Jordi Alonso,
4
Giovanni Apolone,
5
Monika Bullinger,
6
Jakob Bjorner,
7
Shunichi Fukuhara,
8
Stein Kaasa,
9
Alain Leplège,
10
Marianne Sullivan,
11
Sharon Wood-Dauphinee,
12
and John E. Ware, Jr.
1
1
Health Assessment Lab at the Health Institute, New England Medical Center, Boston, Massachusetts;
2
Division of
Psychosocial Research and Epidemiology, The Netherlands Cancer Institute, Amsterdam, The Netherlands;
3
Mapi Research
Institute, Lyon, France;
4
Health Services Research Unit, Institut Municipal d’Investigació Mèdica (IMIM), Barcelona, Spain;
5
Dipartimento di Oncologia, Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy;
6
Abteilung Für Medizinische
Psychologie, Universitätskrankenhaus Eppendorf, Hamburg, Germany;
7
institute of Public Health, University of
Copenhagen, Copenhagen, Denmark;
8
Graduate School of Medicine, The University of Tokyo, Tokyo, Japan;
9
Unit for Applied
Clinical Research, The Norwegian University for Science and Technology, Trondheim, Norway;
10
Institut National de la
Santé et de la Recherche Médicale (INSERM) Unité 292, Hôpital de Bicêtre, Le Kremlin-Bicêtre, France;
11
The Health Care
Research Unit, Institute of Internal Medicine, Sahlgrenska University Hospital and Göteborg University, Göteborg,
Sweden; and
12
School of Physical and Occupational Therapy, Faculty of Medicine, McGill University, Montreal, Canada
ABSTRACT. Increasingly, translated and culturally adapted health-related quality of life measures are being
used in cross-cultural research. To assess comparability of results, researchers need to know the comparability of
the content of the questionnaires used in different countries. Based on an item-by-item discussion among
International Quality of Life Assessment (IQOLA) investigators of the content of the translated versions of the
SF-36 in 10 countries, we discuss the difficulties that arose in translating the SF-36. We also review the solutions
identified by IQOLA investigators to translate items and response choices so that they are appropriate within
each country as well as comparable across countries. We relate problems and solutions to ratings of difficulty and
conceptual equivalence for each item. The most difficult items to translate were physical functioning items that
refer to activities not common outside the United States and items that use colloquial expressions in the source
version. Identifying the origin of the source items, their meaning to American English-speaking respondents and
American English synonyms, in response to country-specific translation issues, greatly helped the translation
process. This comparison of the content of translated SF-36 items suggests that the translations are culturally
appropriate and comparable in their content. J CLIN EPIDEMIOL 51;11:925–932, 1998. © 1998 Elsevier Science Inc.
KEY WORDS. Health status, health-related quality of life, translations, SF-36 Health Survey, cross-cultural
comparisons, IQOLA
INTRODUCTION
Measuring health status is an important component of
national and international health services research and of
increasing interest in clinical practice. A number of health-
status measures have been developed, mostly for use in En-
glish-speaking countries [1]. For use in the growing number
of large multicenter, multicountry trials, as well as to assess
the health status of different cultural groups within a coun-
try, the need for non–English language measures has in-
creased. One approach to meet this need is to translate and
adapt measures originally developed in English for use in a
different cultural context. However, health status measures
developed for use in one country cannot just be translated
into another language; rather, for a questionnaire to be rel-
evant and appropriate in a different setting, cultural adapta-
tion is needed, which may lead to differences between
translated versions and the source questionnaire. Similari-
ties and differences in the content of adapted question-
naires determine the interpretation of results of cross-cul-
tural health status assessments.
As previously described [2–4], the International Quality
of Life Assessment (IQOLA) translation and adaptation
procedure focused on translation of the SF-36 such that
conceptual equivalence with the source version was main-
*Address for correspondence: Anita K. Wagner, Pharm. D., M.P.H.,
Health Assessment Lab, NEMC #345, 750 Washington Street, Boston,
MA 02111.
Accepted for publication on 7 July 1998.