Psychometrics of the Multiple Sclerosis and Magnetic Resonance Imaging Knowledge Patient Questionnaire: A Pilot Study.

Abstract: BACKGROUND: In the last few decades, the revised diagnostic criteria for multiple sclerosis (MS) and the development of numerous new MS therapies have created the possibility of early diagnosis and opportune MS management. However, these changes, and the mounting emphasis on patient choice and shared decision making, have not been accompanied by improvements in information provided to patients with MS (PwMS). Information provision for PwMS increases disease-related knowledge that may assist them in decision making and quality of life. The purpose of this study was to validate the Multiple Sclerosis and Magnetic Resonance Imaging Knowledge Questionnaire (MSMRIKQ) to improve patients' shared decision-making capabilities. METHODS: In this methodological study, the instrument development process was completed in 4 stages using principles of measurement theory: (1) establishing a pool of items after patient and clinician panels' review, (2) evaluating the validity of the scale-both face and content validity, (3) pilot testing the scale, and (4) post-pilot testing statistical analysis of items and scale reliability and validity. RESULTS: The 20-item instrument was finalized based on a panel of MS experts' and patients' comments. The final version of the MSMRIKQ was pilot tested with a sample of 46 PwMS. Face validity was established on all MSMRIKQ items. Individual item-level and scale-level content validity indices for universal agreement estimates were acceptable at item-level content validity index = 1 and scale-level content validity index = 1 for the 20 items. The Kuder-Richardson 20 reliability estimate for the entire scale was 0.58; the Kuder-Richardson 20 estimates for the subscales of MS and magnetic resonance imaging knowledge were 0.35 and 0.51, respectively. The split-half reliability with Spearman-Brown correction for the total scale was 0.60. The Poisson regression model was significant for predicting MS knowledge within this population. CONCLUSION: The MSMRIKQ is a basic knowledge instrument for clinical and research use.