Cross-cultural adaptation and health questionnaires validation: revision and methodological recommendations.

The simple translation of a questionnaire may lead to misinterpretation due to language and cultural differences. When using questionnaires developed in other countries and languages in scientific studies it is necessary, besides the translation, to carry out a cross-cultural adaptation and validation. Our objective was to review the literature on cross-cultural adaptation and validation (CCAV) of health questionnaires, and to synthesize and propose recommendations based on the scientific literature to facilitate this process. The CCAV should follow a systematic process. Two steps are recommended: I) cross-cultural adaptation: direct translation, synthesis, back translation, expert committee consolidation and pre-testing, and 2) validation (with up to seven steps): assessment of internal consistency, reliability, intra- and inter-observer reliability, face, content, criterion and construct validity. Lack of equivalence between questionnaires limits the comparability of results among populations with different cultures and languages and the exchange of information in the scientific community.