A structured questionnaire to assess patient compliance and beliefs about medicines taking into account the ordered categorical structure of data

Rationale, aims and objective The objectives were to describe and evaluate the structured medication questionnaire and to improve data handling of results from the Morisky four-item scale for patient compliance and Beliefs about Medicines Questionnaire-specific (BMQ-specific). Methods A questionnaire was developed with the purpose of being used when identifying medication errors and assessing patient compliance to and beliefs about medicines. Results A majority of the respondents (62%; CI 45-77%) had at least one medication error. Assuming that all items are equally important in the Morisky four-item scale we presented four alternative ways to create a unidimensional global scale. A two-dimensional global scale was also constructed. The results from the BMQ-specific were presented in different ways, all taking into account that the scale has ordered verbal categories: at the level addressing each specific question, at the sub-scales 'concern' and 'necessity' level and at the global level. Conclusions The structured medication questionnaire can be used in daily practice as a tool to identify drug-related problems. The choice of how to use and present data from those scales in research depends on patient characteristics and how discriminating one would like the scales to be.