Cultural Adaptation and Optimization of the Compliance Questionnaire-Rheumatology (CQR) Through Statistical Methods for Patients with Rheumatic Diseases

Abstract

There is a growing interest in the management of long-term conditions and increasing awareness of the need for compliance/adherence's assessment. An inexpensive and simple way to measure patients’ treatment compliance is pharmacoeconomic measurement tools.

The aim of the study is to increase the quality of assessment of patients’ compliance through statistical methods in order to obtain a more accurate estimation and a shorter, easy-to-respond self-administered questionnaire. We used the Compliance Questionnaire-Rheumatology (CQR) translated into Romanian and we verified the reliability and the internal consistency of this instrument. The research included 140 consecutive patients diagnosed with rheumatoid arthritis according to currently used criteria, with different treatment strategies and from different parts of Romania. Two methods for CQR's optimization were used. The first method identified associations between CQR score and patient compliance. An exploratory factor analysis was performed, as an alternative method, to reduce the number of items in CQR.

The factor analysis identified a two-dimensional 9 item model that explains 66.78% of the variance in adherence and has a good internal consistency and fits the data. A shortened and optimized version of the CQR increases the clinical utility by reducing the patient’s burden while maintaining a good level of reliability.