Table 2a.

Clinical measures for fatigue dimensions in non-oncologic medical conditions.

Clinical Measure	Fatigue Dimension(s)	Medical Condition(s)	Statistical Findings
Multidimensional Fatigue Inventory (MFI or MFI-20)		•Amyotrophic Lateral Sclerosis (Abraham and Drory, 2012)
		•Chronic Fatigue Syndrome (Jason et al., 2011; Rowe et al., 2016)
	Physical	•Chronic Obstructive Pulmonary Disease (Antoniu and Ungureanu, 2015; Lewko et al., 2014)
	Mental	•Fibromyalgia (Ericsson et al., 2013; Lukkahatai et al., 2016)
	Cognitive	•Inflammatory Bowel Disease (Norton et al., 2015)	•Intraclass correlation coefficient (ICC) was 0.65–0.84 for MFI subscales (Norton et al., 2015).
	Motivational	•Post-Polio Syndrome (Dencker et al., 2015)	•Internal consistency of the dimensions of the MFI: Cronbach alpha for general fatigue 0.85; physical fatigue 0.86; reduced activity 0.89; reduced motivation 0.68; mental fatigue 0.89. The five-factor rotation of the five facets of the MFI explains a total of 76% of the variance with all factors having eight values of 1 (Goodchild et al., 2008).
	Emotional	•Schizophrenia (Hedlund et al., 2015)	•Cronbach's alpha greater than 0.80 for each of the five subscales (Lukkahatai et al., 2016).
		•Sjogren's Syndrome (Goodchild et al., 2008; van Leeuwen et al., 2015)	•MFI-20 and FIQ correlation r in the following subscales: general fatigue ​= ​0.57; physical fatigue ​= ​0.32; mental fatigue ​= ​0.38; reduced motivation ​= ​0.31; reduced activity ​= ​0.30 (Ericsson et al., 2013).
		•Spondyloarthropathy (Da Costa et al., 2011)	•Test-retest reliability (spearman correlations) for each subscale: general fatigue 0.74; physical fatigue 0.82; reduced activity 0.71; reduced motivation 0.66; mental fatigue 0.91 (Hedlund et al., 2015).
		•Systemic Lupus Erythematosus (Goligher et al., 2008)	•The Cronbach's α coefficients range from satisfactory to good (a ​= ​0.76–0.88) (Da Costa et al., 2011)
Multidimensional Assessment of Fatigue (MAF)	Emotional Cognitive	•Inflammatory Bowel Disease (Norton et al., 2015)
	Mental	•Rheumatoid Arthritis (Balsamo et al., 2014)	•Cronbach's α ​= ​0.96. Distinguishes persons with different levels of fatigue but no fatigue dimension differentiation (Lequerica et al., 2012).
	Motivational	•Systemic Lupus Erythematosus (Goligher et al., 2008)	•Statistically significant difference between experimental and control groups (p ​= ​0.04) (Balsamo et al., 2014).
	Physical	•Traumatic Brain Injury (Lequerica et al., 2012)	•Intraclass correlation coefficient (ICC) was 0.74 for the MAF total score (Norton et al., 2015).
The Revised Piper Fatigue Scale (PFS)	Emotional		•N/A
	Cognitive	•Amyotrophic Lateral Sclerosis (Abraham and Drory, 2012)
	Physical	•Chronic Obstructive Pulmonary Disease (Antoniu and Ungureanu, 2015)
Checklist of Individual Strength (CIS)	Mental	•Ehlers-Danlos Syndrome (Voermans et al., 2011)	•Multiple regression analysis of data of all patients (n ​= ​273) resulted in a model in which pain severity and physical fatigue severity (CIS – fatigue subscale) predicted 31% of functional impairment (p ​< ​0.0001) (Voermans et al., 2010).
	Motivational	•Rheumatoid Arthritis (van Hoogmoed et al., 2010)
	Physical	•Spinal Cord Injury (van Diemen et al., 2016)
Isometric Muscle Strength Test - physiological test of fatigue	Central	•Amyotrophic Lateral Sclerosis (Kent-Braun and Miller, 2000)	•At the end point of exercise for each subject, the maximal voluntary contraction (MVC) was 53 ​± ​10% initial in controls and 43 ​± ​8% initial in ALS, P ​= ​0.06. Tetanic force fell to 43 ​± ​11% in controls and 60 ​± ​8% in ALS, P ​= ​0.01. There was significant central activation failure in ALS that increased markedly during the fatiguing isometric exercise protocol. In contrast, our control group exhibited no central fatigue in response to the same exercise (Kent-Braun and Miller, 2000).
	Peripheral
	Physical
Manchester COPD Fatigue Scale	Cognitive	•Chronic Obstructive Pulmonary Disease (Antoniu and Ungureanu, 2015)	•N/A
	Physical
	Psycho-social
Modified Fatigue Impact Scale (MFIS)	Cognitive	•Inflammatory Bowel Disease (Castillo-Cejas et al., 2013)	•Intraclass correlation coefficient (ICC) values for the test–retest reliability for the MFIS was 0.863. Physical (ICC ​= ​0.860) domain of the MFIS showed good reliability (Learmonth et al., 2013).
	Mental	•Multiple Sclerosis (DeLuca et al., 2008; Learmonth et al., 2013; Penner et al., 2009; Wolkorte et al., 2015)	•In the multiple sclerosis patient group, Cronbach's alpha a ​= ​0.91 for the motor subscale and a ​= ​0.95 for the entire scale. In the control group a ​= ​0.83 for the motor subscale and a ​= ​0.91 for the total scale (Penner et al., 2009).
	Physical	•Myasthenia Gravis (Sabre et al., 2017)	•Significant associations were found between the MFIS cognitive subscale and dual task (DT) costs of 30%-DT accuracy scores (after correction for age; rpartial ​= ​0.60; P ​= ​0.019), 30%-DT reaction times (rpartial ​= ​0.67; P ​= ​0.007), and 10%-DT variability (rpartial ​= ​0.52; P ​= ​0.045). Participants with higher perceived cognitive fatigue presented more DT costs, mainly during the fatiguing (Wolkorte et al., 2015).
Multidimensional Daily Diary of Fatigue-Fibromyalgia-17 (MDF-Fibro-17) instrument	Cognitive	•Fibromyalgia (Li et al., 2017)	•Cronbach's α for the total score and all domain scores (ɑ ​= ​0.94–0.99) (Li et al., 2017).
	Motivational
	Physical
PROMIS Fatigue Fibromyalgia (FM) Profile	Cognitive	•Fibromyalgia (Kratz et al., 2016)	•Pearson correlations between the PROMIS Fatigue FM Profile short forms range from r ​= ​0.60 to 0.77 (i.e., 36–59% shared variance) (Kratz et al., 2016).
	Motivational
	Physical
Brugmann Fatigue Scale (BFS)	Mental	•Sleep Disorder (Mairesse et al., 2017)	•Structure of the Brugmann Fatigue Scale (BFS) comprises both a mental (BFSΨ) and physical fatigue subscale (BFSΦ). Person reliabilities indicate that both the BFSΨ and BFSΦ are able to discriminate between 2 and 3 levels of participants with respect to their subjective propensity to rest (BFSΨ ​= ​.72 and BFSΦ ​= ​.75). The Cronbach's alpha coefficients equal .80 and .77 respectively (Mairesse et al., 2017).
	Physical
Chalder Fatigue Scale	Mental	•Autoimmune Rheumatic Disease (Ali et al., 2017; Huang et al., 2017)	•Cronbach's α ​= ​0.863 (Huang et al., 2017).
	Physical	•Chronic Fatigue Syndrome (Slomko et al., 2020)
Fatigue Assessment Scale (FAS)	Physical	•Post-Sarcoidosis Fatigue Syndrome (Gorski et al., 2017)	•FAS total score correlated significantly and positively with age, Beck Depression Inventory (BDI) score (r ​= ​0.726) and Patient Health Questionnaire-9 (PHQ-9) score (r ​= ​0.788). FAS Physical Fatigue scale score correlated with BDI score (r ​= ​0.670) and PHQ-9 (r ​= ​0.768), while FAS Mental Fatigue scale score was positively associated with age and both BDI (r ​= ​0.702) and PHQ-9 (r ​= ​0.705) scores (Gorski et al., 2017).
Fatigue Impact Scale	Physical	•Bronchiectasis (Hester et al., 2012)	Course participants were found to have
		•Post-Stroke (Boehm et al., 2015)	•Statistically significant (p ​< ​0.05) improvements in scores on the FIS.
		•Chronic Fatigue Syndrome (Slomko et al., 2020)	•There are three subscales covering psychosocial, cognitive, and physical domains; however, no domain differentiation reported (Boehm et al., 2012).
Fatigue Symptom Inventory (FSI)	Physical	•Epilepsy (Hernandez-Ronquillo et al., 2011)	N/A
Health Assessment Questionnaire (HAQ)	Physical	•Psoriatic Arthritis (Husted et al., 2010)	N/A
MG Fatigue Scale (MGFS)	Physical	•Myasthenia Gravis (Jordan et al., 2017)	N/A
Modified Fatigue Impact Scale for Spinal Cord Injury (MFIS-SCI)	Physical	•Spinal Cord Injury (Anton et al., 2017)	•The odds ratio, which is the 95% Confidence Interval (CI), of having a clinically significant MFIS-SCI score at 6-months post discharge were 3.74 times greater in those who had a clinically significant MFIS-SCI at baseline than in those who did not (95% CI ​= ​1.21–12.57) (Anton et al., 2017).
Visual Analogue Scale (VAS)	Physical	•Amyotrophic Lateral Sclerosis (Abraham and Drory, 2012)	•N/A
		•Chronic Stroke (Tseng and Kluding, 2009)
		•Crohn's Disease (van Erp et al., 2017)
		•Fibromyalgia (Ablin et al., 2010)
Mental Fatigue Scale (MFS)	Mental	•Cushing's Syndrome (Papakokkinou et al., 2015)	•N/A
		•Traumatic Brain Injury (Berginström et al., 2017; Palm et al., 2017; Zeng et al., 2016)
Wood Mental Fatigue Inventory (WMFI)	Mental	•Chronic Fatigue Syndrome (Rowe et al., 2016)	•N/A

Note. Column sorting order: For “Clinical Measure,” the most frequently used clinical measure was listed first with the others based on descending frequency. Columns for “Fatigue Dimension(s)” and “Medical Condition(s)” have an A – Z sorting order. “Statistical Findings” column has a randomized sorting.

N/A ​= ​no statistical findings for domain differentiation reported in included articles.