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.