Translation of questionnaires and issues of equivalence

The validity of studies using translated instruments may be questioned when there is a lack of attention to and/or minimal explanation of the procedur es used for determining the equivalence between the primary and secondary l anguage tool. Ensuring equivalence of a translated Chinese version of the M enstrual Distress questionnaire is an important prerequisite fur identifyin g culturally specific expressions of concepts under investigation and for c ross-cultural comparisons. This paper examines the principles and procedure s for determining equivalence of translated tools and their application to the development of an equivalent Chinese version of the Menstrual Distress questionnaire. Translation and back-translation were used to develop a Chin ese version of the Menstrual Distress Questionnaire. Bilingual university s tudents completed both versions of the Menstrual Distress questionnaire. Mo st of the Menstrual Distress Questionnaire items had an acceptable Kappa of >0.4. Intraclass correlation coefficients indicated moderate to high level s of equivalence for total scores and all scales. Improvement in the transl ation of some items is needed to further enhance the equivalence of the Chi nese version of the Menstrual Distress Questionnaire.