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Global Fatigue Index

Last Updated

Purpose

To measure fatigue.

Acronym GFI

Cost

Free

Actual Cost

$0.00

Diagnosis/Conditions

  • Arthritis + Joint Conditions
  • Brain Injury Recovery
  • Cancer Rehabilitation
  • Multiple Sclerosis
  • Pulmonary Disorders

Key Descriptions

  • GFI is derived from 15 of the 16 items of the Multidimensional Assessment of Fatigue (MAF).
  • MAF was originally created for individuals with rheumatoid arthritis (Belza et al, 1993)
  • Measures fatigue across four dimensions:
    -Severity (items 1-2)
    -Distress(item 3)
    -Impact of fatigue on various activities of daily living (items 4-14)
    -Timing of fatigue (item 15)
  • Self-administered questionnaire
  • Scoring responses for MAF:
    -Items 1, 4-14: numerical responses: 1 = not at all to 10 = a great deal
    -Item 2: numerical responses: 1= mild to 10=severe
    -Item 3: numerical responses: 1=no distress to 10= a great deal of distress
    -Items 15 and 16: categorical response 1-4
    -Do not assign a score to items 4-14 if the respondents have a response of “do not do any activity for reasons other than fatigue.”
    -Assign a zero to items 2-16 if a respondent selects “no fatigue” on item 1.
    -The higher the score, the more severe the fatigue
  • Scoring responses for GFI:
    -Item 16 of the MAF is not included in the GFI
    -Convert item 15 to 0-10 scale by multiplying each score by 2.5
    -Sum items 1, 2, and 3 and average 4-14, and 15
    -Do not assign a score to items 4-14 if the respondents have a response of “do not do any activity for reasons other than fatigue.”
    -Assign a zero to items 2-16 (item 16 is not included in the GFI) if a respondent selects “no fatigue” on item 1.
    -Scores range from 1 (no fatigue) to 50 (severe fatigue)

Number of Items

15

Equipment Required

  • Paper
  • Pencil

Time to Administer

5 minutes

Required Training

No Training

Instrument Reviewers

Initially reviewed by Irene Ward, PT, DPT, NCS and the TBI EDGE task force of the Neurology Section of the APTA in 9/2012

ICF Domain

Body Structure
Body Function
Participation

Professional Association Recommendation

Recommendations for use of the instrument from the Neurology Section of the American Physical Therapy Association’s Multiple Sclerosis Taskforce (MSEDGE), Parkinson’s Taskforce (PD EDGE), Spinal Cord Injury Taskforce (PD EDGE), Stroke Taskforce (StrokEDGE), Traumatic Brain Injury Taskforce (TBI EDGE), and Vestibular Taskforce (VEDGE) are listed below. These recommendations were developed by a panel of research and clinical experts using a modified Delphi process.

 

For detailed information about how recommendations were made, please visit:  

Abbreviations:

 

HR

Highly Recommend

R

Recommend

LS / UR

Reasonable to use, but limited study in target group / Unable to Recommend

NR

Not Recommended

 

Recommendations based on level of care in which the assessment is taken:

 

Acute Care

Inpatient Rehabilitation

Skilled Nursing Facility

Outpatient

Rehabilitation

Home Health

TBI EDGE

NR

LS

NR

R

LS

 

Recommendations for use based on ambulatory status after brain injury:

 

Completely Independent

Mildly dependant

Moderately Dependant

Severely Dependant

TBI EDGE

N/A

N/A

N/A

N/A

 

Recommendations for entry-level physical therapy education and use in research:

 

Students should learn to administer this tool? (Y/N)

Students should be exposed to tool? (Y/N)

Appropriate for use in intervention research studies? (Y/N)

Is additional research warranted for this tool (Y/N)

TBI EDGE

No

No

Yes

Not reported

Considerations

  • The GFI is largely derived from the MFA.
  • Articles routinely report the lack of uniformity in defining fatigue in TBI which may contribute to weaknesses in this measure’s validity.

Do you see an error or have a suggestion for this instrument summary? Please e-mail us!

Brain Injury

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Cut-Off Scores

Traumatic Brain Injury: (Cantor et al, 2008, n=223 individuals with mild to severe TBI and 85 noninjured controls. For the TBI group: 52.5% male and 47.5% female, age=47.8(SD 12.1), time since injury= 15.0(SD=13.2) years.)

  • Using a cut-off score of 21 on the GFI, chi-square test results indicate that 75% of individuals with TBI had statistically significant fatigue as compared to 40% of those in the control group (chi square (df=1, n=308)=34.05, P< 0.001).

 

Traumatic Brain Injury: (Englander et al, 2010, n=119 individuals at least 1 year post-TBI, 80 males, mean age=40±12 years, time since injury=9±7.6 years)

  • Used a cut-off score of 27 and above for the presence of fatigue for the GFI. 53% of the participants scored in the abnormal range of the GFI (>27).

Normative Data

Traumatic Brain Injury: (Bushnik T et al, 2007, n=64, average age=42 yo (SD=12; range=16-66 years) and duration of injury=10 years (SD=8; range=1.2-31 years)

  • Average GFI 24.4 (SD=11.7)

 

Traumatic Brain Injury: (Cantor et al, 2008, n=223 individuals with mild to severe TBI and 85 noninjured controls. For the TBI group: 52.5% male and 47.5% female, age=47.8(SD 12.1), time since injury= 15.0(SD=13.2) years.)

  • Average GFI for TBI group 28.361±11.280
  • Average GFI for control group 19.972±10.618

GFI Scores Across Samples (this table is from the MAF User's Guide)

 

 

 

 

Reference (alphabetically)

Condition

Sample Size

Mean (SD)

Cronbachs Alpha

Belza, 1995

Healthy Controls

51

17.0(11.13)

.93

Belza, 1995

Rheumatoid Arthritis

46

29.2(9.9)

.93

Bormann et al, 2001

HIV + adults

209

23.8(13.48)

.96

Grady et al, 1998

HIV + adults w/IL-2HIV+ adults

28; 22

11.5(10.8); 12.6 (13.6)

NR

Wambach et al, 1998

Breastfeeding women

41

23.51 (11.05)

.89-.93

Williams et al 1999

Postpartum women

74

Grp 1 26.43 (12.07)

Grp 2

27.44 (11.51) @

.91-.92

* Only baseline scores presented

# Two measurement points: when fatigue was expected to be high and when it was expected to be low

@ Group 1 = mothers with newborns on apnea monitors; Group 2 = mothers with newborns not on apnea monitors

 

 

 

 

Construct Validity

Convergent Validity:

Traumatic Brain Injury: (Bushnik et al, 2007, n=64, average age=42 yo (SD=12; range=16-66 years) and duration of injury=10 years (SD=8; range=1.2-31 years)

  • There was a trend towards an association between lower basal cortisol levels and higher Fatigue Severity Scale scores (Spearman’s ρ=-0.231; p=0.067) and higher GFI scores (Spearman’s ρ=-0.235; p=0.063). Note: It was expected that lower cortisol levels would result in more fatigue.

 

Traumatic Brain Injury: (Ashman et al, 2008, n=202 mild to severe TBI and 73 individuals with no disability. For the TBI group: 109 males, 93 females; age= 47.7 (SD=12.3); time since injury 14.7(SD=13.4) years.)

  • GFI was associated with response speed factor scores in neuropsychological testing at time 1 (T1) and time 3 (T3) (T1:r=-0.18, P<.01; T3:r=-0.15, P=.03).

Mixed Populations

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Normative Data

GFI Scores Across Samples (this table is from the MAF User's Guide)

 

 

 

 

Reference (alphabetically)

Condition

Sample Size

Mean (SD)

Cronbachs Alpha

Belza, 1995

Healthy Controls

51

17.0(11.13)

.93

Belza, 1995

Rheumatoid Arthritis

46

29.2(9.9)

.93

Bormann et al, 2001

HIV + adults

209

23.8(13.48)

.96

Grady et al, 1998

HIV + adults w/IL-2HIV+ adults

28; 22

11.5(10.8); 12.6 (13.6)

NR

Wambach et al, 1998

Breastfeeding women

41

23.51 (11.05)

.89-.93

Williams et al 1999

Postpartum women

74

Grp 1 26.43 (12.07)

Grp 2

27.44 (11.51) @

.91-.92

* Only baseline scores presented

# Two measurement points: when fatigue was expected to be high and when it was expected to be low

@ Group 1 = mothers with newborns on apnea monitors; Group 2 = mothers with newborns not on apnea monitors

 

 

 

 

Internal Consistency

HIV+ adults: (Bormann et al, 2001. n=209 HIV+ and symptomatic adults)

  • Excellent internal consistenty, Cronbach’s alpha = .96
  • The GFI score did not change significantly within an 8 week period indicating stability

Construct Validity

Convergent Validity:

HIV+ adults: (Bormann et al, 2001; n=209 HIV+ and symptomatic adults)

  • Adequate Pearson’s correlations with the BDI, Perceived Stress Scale, Health Distress Scale, Illness Intrusiveness Scale, and number of days spent in bed all had significant relationships at or above .51, p<.001
  • Excellent, GFI correlated inversely with SF-36 physical health summary scores (r=-.79, p<.001) and SF-36 mental health summary scores (r=-.74, p<.001). The poorer the physical or mental health, the greater the fatigue.

 

Discriminant Validity:

HIV+ adults: (Bormann et al, 2001. n=209 HIV+ and symptomatic adults)

  • 2 item vitality subscale from SF-36, had a high inverse relationship with the GFI (r=-.80, p<.001)
  • GFI highly correlated with HIV Self-Efficacy fatigue subscale (r=-.64, p<.001)
  • The higher the self-efficacy in managing the fatigue, one reports less fatigue

Face Validity

Cantor et al reports “the GFI is one of the most widely used measures of fatigue.”

Bibliography

Ashman, T. A., Cantor, J. B., et al. (2008). "Objective measurement of fatigue following traumatic brain injury." J Head Trauma Rehabil 23(1): 33-40. 

Belza, B. L. (1995). "Comparison of self-reported fatigue in rheumatoid arthritis and controls." J Rheumatol 22(4): 639-643. 

Belza, B. L., Henke, C. J., et al. (1993). "Correlates of fatigue in older adults with rheumatoid arthritis." Nurs Res 42(2): 93-99. 

Bormann, J., Shively, M., et al. (2001). "Measurement of fatigue in HIV-positive adults: reliability and validity of the Global Fatigue Index." J Assoc Nurses AIDS Care 12(3): 75-83. 

Bushnik, T., Englander, J., et al. (2007). "Fatigue after TBI: association with neuroendocrine abnormalities." Brain Inj 21(6): 559-566. 

Cantor, J. B., Ashman, T., et al. (2008). "Fatigue after traumatic brain injury and its impact on participation and quality of life." J Head Trauma Rehabil 23(1): 41-51. 

Englander, J., Bushnik, T., et al. (2010). "Fatigue after traumatic brain injury: Association with neuroendocrine, sleep, depression and other factors." Brain Inj 24(12): 1379-1388. 

Grady, C., Anderson, R., et al. (1998). "Fatigue in HIV-infected men receiving investigational interleukin-2." Nurs Res 47(4): 227-234. 

Wambach, K. A. (1998). "Maternal fatigue in breastfeeding primiparae during the first nine weeks postpartum." J Hum Lact 14(3): 219-229. 

Williams, P. D., Press, A., et al. (1999). "Fatigue in mothers of infants discharged to the home on apnea monitors." Appl Nurs Res 12(2): 69-77.