The evaluation of patient-centered care interventions relies on tools that measure patient-reported outcomes (PROs) [1]. A PRO is designed, and its validity documented [2], for specific settings and the language in which it was developed. To be used outside its original setting, it must undergo translation and cultural adaptation [3]. There are several advantages in adapting an existing questionnaire: it is quicker, cheaper, and easier to undertake adaptation rather than creating a new one. A robust questionnaire available in several languages permits international studies and comparison across languages [3], [4].
The aim of adaptation is to generate a version of the questionnaire that returns data that are equivalent to the original. The process should avoid the introduction of bias and inaccuracies. For example, a scale could be translated in different ways: Good, fair, and poor could be translated in French to bon, moyen, and mauvais or, alternatively, bon, médiocre, and mauvais because fair has two possible translations with different intensity and would elicit different answers [5]. Challenges of translation include faux-amis (false friends) which are prone to mistranslations and a word-to-word translation of an expression can lead to a nonsense [4].
A recent review [6] identified 17 translation and cultural adaptation processes. For example, the World Health Organization or Guillemin and Beaton [3], [4], [7], [8] recommend forward translation, back-translation, and expert committees. The back-translation is the original language generated from the target language [3], [7], [9].
The purpose of the back-translation is to highlight discrepancies between the source document and the translation. It permits a greater involvement of the original author [4], [10]. The back-translation step is generally considered best practice and produces a satisfactory result despite being time consuming and expensive [11], [12]. The back-translation may, however, introduce errors and bias or correct them in situations where the back-translator identifies a forward translator error. There is currently no rigorous evidence of the value of the back-translation in questionnaire adaptation, leading to suggestions that it could be omitted [4], [5], [8], [9], [10], [13], [14].
Guillemin and Beaton advocate that a multidisciplinary committee should discuss the back-translation, synthesizing the previous phases of translation and back-translation and correcting errors. This step is considered central for cultural adaptation and producing a consensual forward translation [3], [7]. However, a multidisciplinary committee may not change the outcome, suggesting that the procedure could be further simplified [13], [14].
Few studies have compared cultural adaptation approaches [6], [9], [13], [14], and no robust experiment demonstrates the value of back-translations or committees. We therefore translated and culturally adapted a well-validated English questionnaire, the Health Education Impact Questionnaire (heiQ) [15], [16], used widely in the evaluation of chronic disease self-management and health education programs [16], a rapidly growing field.