Translation and cultural adaptation of quality of life questionnaires: an evaluation of methodology.

OBJECTIVE

To evaluate the methodological steps currently proposed in translation and cultural adaptation of quality of life questionnaires.

METHODS

Fifty patients with rheumatoid arthritis were invited to participate. Two versions each of the Stanford Health Assessment Questionnaire (HAQ), the MOS 36 Item Short-Form Health Survey (SF-36), and the Arthritis Impact Measurement Scales 2 (AIMS-2) were administered: version 1 was a literal translation of the questionnaire; version 2 resulted from a process of translation and cultural adaptation following internationally accepted guidelines. For each patient we applied 2 questionnaires before and after consultation. The questionnaire, the order of administration, and the version were randomly assigned. The interviews were performed by a single interviewer. Several clinical and laboratory outcome measures were assessed simultaneously. Descriptive statistical analysis was used to characterize the data. Spearman and intraclass correlation coefficients were used to evaluate reliability and validity of each version of each questionnaire.

RESULTS

Patients' mean (SD) age was 47 (12) years and mean (SD) disease duration was 10 (7) years. The differences of the mean in the physical and affective AIMS-2 components between the literal and adapted versions (0.21 and 0.11, respectively) were similar to the differences in the intraobserver application of the same version of culturally adapted AIMS-2 components (0.03 and 0.20) (the component scores range from 0 to 10). The same results were observed when considering other components of AIMS and SF-36, as well as HAQ scores. Version 1 and 2 presented a similar clinically and statistically significant correlation with clinical and laboratory measures used in the validation process of the questionnaires.

CONCLUSION

The complex methodologies proposed in the translation and validation of the questionnaires should be carefully reevaluated. The simplification of this methodology should be studied.