Development and Validation of the Medication Adherence Scale for Iraqi Patients with Rheumatoid Arthritis (MASIPRA): A Cross-Sectional Study.

BACKGROUND

Adherence to disease-modifying anti-rheumatic drugs (DMARDs) is essential to ensure optimum benefit for rheumatoid arthritis (RA) patients. However, adherence to DMARDs was suboptimal worldwide, especially in developing countries like Iraq. Many adherence scales are available to help healthcare providers assess RA patients' adherence to their prescribed therapies; however, such tools are often generic, lengthy, unavailable in Arabic, or not freely accessible.

OBJECTIVE

To develop and validate the Medication Adherence Scale for Iraqi Patients with Rheumatoid Arthritis (MASIPRA) and examine its psychometric properties.

METHODS

The Medication Adherence Scale for Iraqi Patients with Rheumatoid Arthritis was developed based on previously validated scales with cultural adaptation. It consists of ten items rated on a 5-point Likert scale. Content validity of MASIPRA was done by a panel of seven experts. Clarity of the scale items was established through testing on ten RA patients. Reliability of MASIPRA was confirmed through testing internal consistency (Cronbach's alpha) and test-retest reliability. Convergent validity was established by correlating the total MASIPRA score with an already validated scale, the Morisky Medication Adherence Scale-4 (MMAS-4). Concurrent validity was confirmed by correlating the MASIPRA score with the RA clinical disease activity index (CDAI).

RESULTS

MASIPRA showed good internal consistency (Cronbach's alpha=0.804) and test-retest reliability (r=0.804, p< 0.001). It was strongly and significantly correlated with MMAS-4 (r=0.863, p< 0.001) and significantly but inversely correlated with CDAI (r = -0.278, p=0.005). Compared with the MMAS-4, the MASIPRA showed higher sensitivity and specificity in discriminating RA patients according to their disease activity.

CONCLUSION

The MASIPRA is a brief, reliable, and valid instrument for assessing adherence to DMARDs among Iraqi patients with RA.