A self-administration questionnaire was used to obtain the data from schoolchildren and their parents. The questionnaire consisted of a list of belief items and general knowledge questions about medicines, which were developed based on item formulation and taken from published questionnaires from scientific literature and based on the ‘Guide to Developing and Evaluating Medicine Education Programmes and Materials for Children and Adolescents’ (USP Ad Hoc Advisory Panel on Children and Medicines, 1998). According to this guide, children in the age group of 7–12 years should be known about the therapeutic purposes of medicines, the difference between medicines for children and medicines for adults, the side effects of medicines and that the efficacy of medicines is not related to their colour, size, taste and dosage form. The face and content validity were measured by an expert in child development and education. The readability of the questionnaire was pretested with a group of children and their teachers to ensure the clarity of the items. Furthermore, the teachers explained the items for their students before filling the questionnaire. The parents’ questionnaire contained questions on the socio-demographic charac- teristics of the parents to identify their educational level and the socio-economic status (SES) of the family.
The data were collected from the children and their parents using self-administrated question- naires in two languages (Malay and English) to make the questions easier and more understandable for children. However, two questionnaires were used in the survey, one for the child and the second for his/her parents. Both questionnaires were given the same code for each child to match and mea- sure the association between children’s beliefs and their parent’s characteristics. The question- naires were distributed to all children and filled up during the school session and returned to their teachers immediately upon completion. The parents’ questionnaire was handed to all parents through their children to fill up and collected the next day. For more accuracy, the children’s ques- tionnaire was ignored if there were missing data in their parents’ questionnaire.