The Multidimensional Fatigue Inventory

Posts have been copied from this thread about a study that used the MFI.

The intro to the linked MFI questionnaire says

Does anyone know what validation study they refer to? Because, applied to ME, some of the MFI questions are extremely open to different interpretations. Not to mention patronisingly phrased, e.g. what has 'feeling' to do with anything in for example "Physically, I feel only able to do a little"? This MFI, like most other questionnaires, should never have passed validation for ME.

 

Well this paper is referenced at the bottom of the linked questionnaire, so presumably it is this one

The multidimensional Fatigue Inventory (MFI) psychometric qualities of an instrument to assess fatigue

Abstract
The Multidimensional Fatigue Inventory (MFI) is a 20-item self-report instrument designed to measure fatigue. It covers the following dimensions: General Fatigue, Physical Fatigue, Mental Fatigue, Reduced Motivation and Reduced Activity. This new instrument was tested for its psychometric properties in cancer patients receiving radiotherapy, patients with the chronic fatigue syndrome, psychology students, medical students, army recruits and junior physicians. We determined the dimensional structure using confirmatory factor analyses (LISREL's unweighted least squares method). The hypothesized five-factor model appeared to fit the data in all samples tested (AGFIs > 0.93). The instrument was found to have good internal consistency, with an average Cronbach's alpha coefficient of 0.84. Construct validity was established after comparisons between and within groups, assuming differences in fatigue based on differences in circumstances and/or activity level. Convergent validity was investigated by correlating the MFI-scales with a Visual Analogue Scale measuring fatigue (0.22 < r < 0.78). Results, by and large, support the validity of the MFI.

Paywall, https://www.sciencedirect.com/science/article/abs/pii/002239999400125O

 

This 2017 paper by Murdock et al evaluated the MFI-20 in ME and reported ceiling effects, and problems with validity and reliability. From the abstract:

The general and physical fatigue subscales on Multidimensional Fatigue Inventory-20, as well as the role of physical health on the RAND SF-36, demonstrated questionable or unacceptable internal consistency and problematic ceiling effects.

Significant ceiling effects and concerns with reliability and validity were observed among Multidimensional Fatigue Inventory-20 and RAND SF-36 subscales for ME/CFS patients.​

 

Here is a link to the full article cited above :

www.readcube.com/articles/10.1007/s11136-016-1406-3?shared_access_token=uJCUPIecRN788WfAHxrzzfe4RwlQNchNByi7wbcMAY7yGjsjRnmV8ZBFwoldRsMrb5lYaWTqHg9IdRBx13mhZY9GtRTOWTbcTJwoU8HUdtElsIWQXm7DotKzuBNeBfub86s1g5agLJP0n1ovBB11babf284yLC38grg1J5DHyCM%3D