Psychometric properties of the multidimensional fatigue inventory in people with type 2 diabetes mellitus

Sarah Parveen; Muhammad Azharuddin; Chhavi Arora Sehgal; Maria Usmani; Majumi Mohamad Noohu

Sarah Parveen Centre for Physiotherapy and Rehabilitation Sciences, Jamia Millia Islamia, New Delhi, India
Muhammad Azharuddin Department of Physiotherapy, Regional Institute of Paramedical and Nursing Sciences, Aizawl, Mizoram, India
Chhavi Arora Sehgal Centre for Physiotherapy and Rehabilitation Sciences, Jamia Millia Islamia, New Delhi, India
Maria Usmani Centre for Physiotherapy and Rehabilitation Sciences, Jamia Millia Islamia, New Delhi, India
Majumi Mohamad Noohu Centre for Physiotherapy and Rehabilitation Sciences, Jamia Millia Islamia, New Delhi, India

Keywords: fatigue, type 2 diabetes mellitus, reliability, validity, depression

Abstract

The purpose of this study was to examine the test-retest reliability and discriminant validity of the Multidimensional Fatigue Inventory (MFI) in people with type 2 diabetes mellitus (T2DM). The study recruited 30 people with T2DM. Test-retest reliability of the MFI was examined by re-administration of the MFI after an interval of one day. Cronbach’s α, intraclass correlation (ICC), standard error of measurement (SEM), and smallest detectable change (SDC) were calculated. Bland-Altman limits of agreement (LoA) were determined. Discriminant validity was assessed using Spearman’s test. Internal consistency values were adequate for the MFI-total score and five MFI subscales, with Cronbach’s α ranging from 0.97 to 0.99. ICCs ranged from 0.97 to 0.99. The Bland-Altman analysis revealed high stability and low variation of MFI. High discriminant validity was observed for MFI (r=0.33, p=0.08). In order to measure the different aspects of fatigue in people with T2DM, MFI can be considered a comprehensive instrument.