Pittsburgh Fatigability Scale


Fatigue is a very common symptom in older adults and is strongly associated with disability and mortality, but studying fatigue is difficult because of its subjective, qualitative nature. Characterizing fatigability allows us to describe one’s susceptibility to experiencing fatigue in the context of a quantifiable demand at a fixed intensity and duration. We recognized a gap in knowledge that no single tool existed to measure perceived fatigability in older adults. It was important to develop a validated paper-and-pencil test as an alternative for epidemiologic research because performance measures:

  1. Are costly and time consuming.
  2. Have requirements of in person visits, dedicated space and staff – not always practical for many research and clinical settings.
  3. Cannot be administered to very old and frail adults unable to do physical performance testing.

In 2011, Dr. Glynn pioneered work to design and validate the Pittsburgh Fatigability Scale (PFS, Copyright 2014, University of Pittsburgh). The PFS is a 10-item, self-administered questionnaire that assesses self-report whole-body physical and mental tiredness related to activities of fixed intensity and duration in adults age ≥60. The PFS improves upon and overcomes deficiencies in existing self-report fatigue tools by anchoring fatigue to set demand activities. This is especially important when studying older adults, who in an effort to reduce or avoid fatigue may modify their exertion (self-pace) to maintain a tolerable effort. Funding for this seminal research was secured from a Pittsburgh Claude D. Pepper Older Americans Independence Center Developmental Pilot Grant (P30 AG024826) and NIH Intramural Research Program support.

Available Languages:

  • Chinese (Mainland)
  • Chinese (Traditional)
  • Danish
  • Dutch
  • English
  • French
  • German
  • Indian (Telugu)
  • Korean
  • Catalan (Spain)
  • Spanish (Spain)
  • Spanish (US)

*The PFS can be translated into additional languages with approval from the University of Pittsburgh. Please use the form at the bottom of the page to get the process started.

Use of the PFS in cohort studies and clinical trials:

  • Baltimore Longitudinal Study of Aging (BLSA)
  • Long Life Family Study
  • The Osteoporotic Fractures in Men (MrOS)
  • MRC National Survey of Health and Development- 1946 British Cohort
  • Danish Healthy Ageing Network of Competences (HANC) Study
  • Mobility and Independent Living in Elders (MILES) Study
  • International Study of Elders in Rural India
  • Stony Brook University World Trade Center Health Program
  • Study of Muscle, Mobility, and Aging (SOMMA)
  • PFS: SITLESS Study
  • ENRGISE Study
  • Effect of Thyroid Hormone Replacement on Fatigability in Untreated Older Adults with Subclinical Hypothyroidism (TRUST FATIGUE) Study
  • Nitrite Benefits to Mediate Fatigability in Older Heart Failure with Preserved Ejection Fraction Patients study and the Mobility & Vitality Lifestyle Program

Selected Publications:
Validation studies

  • The Pittsburgh Fatigability scale for older adults: development and validation. (link)
  • Validation of Perceived Mental Fatigability Using the Pittsburgh Fatigability Scale. (link)
  • Validation of the Spanish version of the Pittsburgh Fatigability Scale for older adults. (link)
  • Translation and validation of the Dutch Pittsburgh Fatigability Scale for older adults. (link)
  • Validation of the Traditional Chinese Version of the Pittsburgh Fatigability Scale for Older Adults. (link)
  • Psychometric properties of the Korean version of the Pittsburgh Fatigability Scale in breast cancer survivors (link)
  • Validation of perceived physical fatigability using the simplified-Chinese version of the Pittsburgh Fatigability Scale (link)

Key papers lead/co-authored by Glynn group

  • Fatigability: A Prognostic Indicator of Phenotypic Aging (link)
  • Response to: Comment on: Fatigability: A Prognostic Indicator of Phenotypic Aging. (link)
  • Pittsburgh Fatigability Scale: One-Page Predictor of Mobility Decline in Mobility-Intact Older Adults. (link)
  • Epidemiology of Perceived Physical Fatigability in Older Adults: The Long Life Family Study (link)
  • Prevalence and severity of perceived mental fatigability in older adults: The Long Life Family Study. (link)
  • Evaluation of the Bidirectional Relations of Perceived Physical Fatigability and Physical Activity on Slower Gait Speed (link)
  • Profiles of Accelerometry-Derived Physical Activity Are Related to Perceived Physical Fatigability in Older Adults. (link)
  • Are BMI and inflammatory markers independently associated with physical fatigability in old age? (link)
  • Validation of Gait Characteristics Extracted From Raw Accelerometry During Walking Against Measures of Physical Function, Mobility, Fatigability, and Fitness. (link)
  • Neural correlates of perceived physical and mental fatigability in older adults: A pilot study. (link)
  • Assessing fatigability in mobility-intact older adults. (link)
  • Strong Relation between Muscle Mass Determined by D3-creatine Dilution, Physical Performance and Incidence of Falls and Mobility Limitations in a Prospective Cohort of Older Men. (link)
  • The Association between Poor Diet Quality, Physical Fatigability and Physical Function in the Oldest-Old from the Geisinger Rural Aging Study. (link)
  • Randomized Controlled Trial of Exercise to Improve Walking Energetics in Older Adults. (link)
  • Perceived physical fatigability improves after an exercise intervention among breast cancer survivors: a randomized clinical trial (link)

Tools/Materials (available upon request):

Please download, complete and email this form to receive additional materials


The PFS may only be used for non-commercial education and research purposes. If you would like to use the PFS instrument for commercial purposes or for commercially sponsored research, please contact the Office of Technology Management at the University of Pittsburgh at 412-648-2206 for licensing information.

Copyright 2014, University of Pittsburgh. All rights reserved. Developed by Glynn NW, Santanasto AJ, Simonsick EM, Boudreau R M, Beach SR, Schulz R, Newman AB of the University of Pittsburgh using National Institute of Health Funding.


Glynn NW, Santanasto AJ, Simonsick EM, Boudreau RM, Beach SR, Schulz R. Newman AB.: J Am Geriatr Soc. 2015. Jan;63(1): 130-5.


Nancy W Glynn, PhD
Associate Professor, Epidemiology
Director, Master's Degree Programs, Epidemiology