Psychometric properties of the adherence questionnaire in patients with chronic disease: A mix method study

Introduction: Non-compliance is a concern to all healthcare disciplines especially in patients with chronic illness that is caused by social factors. For determining the factors affect on patients' health, it is essentialto understand the meaning of compliance and its measurement which lead to improve compliance. However, there is not any instrument to assess compliance of all dimensions of treatment in patients with chronic disease in Iranian context. The purpose of this study was to develop and psychometric properties of compliance questionnaire. Materials and Methods: This study was conducted by triangulation approach in two concept analysis and methodological research sequential phases. In first part, Hybrid Model concept analysis was used to explore the meaning of compliance and to generate questionnaire items, and in second part psychometric properties was used to evaluate the validity and reliability of a compliance instrument.First, in theoretical phase of Hybrid Model concept analysis, data was collected by using literature reviews to develop a working definition. Second in field work phase qualitative data obtained through semi-structure interviews withparticipatingof 6 patients diagnosed with chronic disease. Third, in analytical phase, integration and reanalysis of the data gained during two former phases of concept analysis was conductedusing directed qualitative content analysis. In second part, a primary questionnaire was created by using the results of research. In the third part, the psychometric properties including face validity, content validity, construct validity, internal consistency, and test-retest reliability was measured. Results: The process of concept analysis in theoretical phase resulted in extracting 11 categories,in field work phase seven categories and in third phaseeight themes emerged. 127 items was extracted.The psychometric property was carried out as a result the 127-item questionnaire was modified and the items decreased to 48. The result of exploratory factor analysis showed that this questionnaire contains 7 factors including making effort for treatment, intention to take the treatment, adaptability, integrating illness into life, stick to the treatment, commitment to treatment and indecisiveness for applying treatment and the items decreased to 40. The 7 factors explained nearly 48.514 of the variance of the questionnaire. The reliability was carried out by using test-retest reliability andCronbach'salpha 0.92. Conclusion: These findings offer helpful insights into the meaning of compliance and provide an instrument to assess the adherence of patients with chronic disease. The Adherence Questionnaire appears to be an appropriate tool for providing reliable and valid data to determine compliance in adult patients with chronic disease in Iranian context. © 2018, Semnan University of Medical Sciences. All rights reserved