Hamid Allahverdipour
1,2* 
, Majid Badri
2, Abdolreza Shaghaghi
2 , Hassan Mahmoodi
3 , Haleh Heizomi
2 , Shayesteh Shirzadi
4 , Mohammad Asghari-Jafarabadi
5,6,7,8 1 Research Center of Psychiatry and Behavioral Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
2 Health Education & Promotion Department, Tabriz University of Medical Sciences, Tabriz, Iran
3 Social Determinants of Health Research Center, Research Institute for Health Development, Kurdistan University of Medical Sciences, Sanandaj, Iran
4 Department of Public Health, Neyshabur University of Medical Sciences, Neyshabur, Iran
5 Cabrini Research, Cabrini Health, Malvern, VIC, 3144, Australia
6 School of Public Health and Preventative Medicine, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, VIC, 3004, Australia
7 Department of Psychiatry, School of Clinical Sciences, Faculty of Medicine, Nursing and Health Sciences, Monash University, Clayton, VIC, 3168, Australia
8 Road Traffic Injury Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
Abstract
Background: Proper elucidation of medication non-adherence reasoning especially in older adults might pave the way for an auspicious therapeutic outcome. The main aim of this study was to develop and psychometrically test the Medications Non-adherence Reasoning (MedNARS) questionnaire for application in research and probably practice settings.
Methods: A mixed methods design was utilized to develop the MedNARS. The item pool was mainly generated based on a qualitative query and literature review. The expert panel approved version of the MedNARS was psychometrically assessed on a convenience sample of 220 older patients with chronic disease. The internal consistency, test-retest reliability, content and face validity of the scale were appraised and its construct validity was assed using exploratory and confirmatory factor analyses.
Results: A nine-item version of the MedNARS was drafted based on the classical item analysis procedures and its estimated internal consistency measure of the Cronbach’s alpha (0.85) and test-retest reliability (0.96) were in the vicinity of acceptable range. The exploratory factor analysis (EFA) output revealed a unidimensional structure for the MedNARS and the conducted confirmatory factor analysis (CFA) indicated an acceptable data fit for the extracted one-factor model. The goodness of fit indices were as the followings: χ2 /df=1.63(90% CI: 0.02 to 0.11), root mean squared error of approximation (RMSEA)=(0.07), comparative fit index (CFI)=0.95, Tucker–Lewis index (TLI)=0.93 and standardized root mean squared residual (SRMSR)=(0.05).
Conclusion: The study findings were indicative of MedNARS’s applicability and feasibility for use in assessment of medication non-adherence reasoning among the elderly patients with chronic diseases. The MedNARS as a brief and elder-friendly instrument can be applied both in research and practice settings to enhance efficiency, safety, and health outcomes of the therapeutic recommendations.