Measuring quality of life in different cultures: translation of the Functional Living Index for Cancer (FLIC) into Chinese and Malay in Singapore

Quality-of-life assessment has become an accepted method of evaluation in clinical medicine. The technique is based on a patient's self-assessment of physical, psychological, and social function, as well as the effects of distressing physical symptoms. The most important aspect of quality-of-life assessment is that it brings into focus a patient-centred view of health outcome, which is broader than the physiologic measures which predominate in Western medicine. Strategies for the development and use of assessment questionnaires have evolved over the past 15 years, and numerous questionnaires have been created. Most originate in Western societies, with English as the most common language of development. Adapting such questionnaires for use in other language and cultural settings is an imprecise practice. Language translation and equivalent cultural meaning must both be addressed. This paper reports on the language translation process and results for the Functional Living Index for Cancer (FLIC) as translated into Chinese and Malay in Singapore. We employed a step-wise process beginning with translation/back translation, followed by structured pilot field trials and population sampling. Taped versions of the questionnaire were devised to meet illiteracy problems in the sample population. Paired comparisons of the Chinese and Malay versions of individual questions with their English counterparts show good correlations and similar means most of the time. Factor analysis on a population sample of 246 (112 Chinese, 35 Malay and 98 English speaking) with cancers of minimal, extensive or palliative extent is convergent with that obtained on a North American population. However, a separate analysis of the Chinese questionnaires showed some differences in factor pattern. Specific language and cultural translation difficulties are discussed. Of note is the predicted significant decrease in total FLIC scores with extent of disease within each of the language preference populations, which provides some evidence for the validity for each language version in the Singapore culture(s). Thus, the FLIC translations into Malay and Chinese in Singapore can be considered for use in local trials, subject to ongoing evaluation.