Methods: The English-language validated questionnaires using data about demographics and monthly health records were translated into the Chinese language. Both forward and backward translated versions were validated.
Results: The developed demographic and monthly health questionnaires showed an overall item-level content validity index (I-CVI) of 0.99 and 0.97, respectively; while the translated Chinese versions showed I-CVI of 0.97 and 0.98, respectively. Item-level of response process validity index of 1.00 for this questionnaire was obtained from 30 respondents inferring that the items were clear and comprehensible.
Conclusions: This study showed acceptable levels validity in the Chinese translated version, illustrating a valid and reliable tool to be used for simultaneous assessment of gastrointestinal and respiratory tract-related illnesses in young children that is applicable for Malaysia's Chinese population and other Chinese-speaking nations.