The Functional Status Score-Intensive Care Unit (FSS-ICU) is an eight-point assessment of ICU patient physical function. Each task is evaluated on an ordinal scale ranging from 0 (unable to perform) to 7 (complete independence). The total score ranges from 0-35, with higher scores indicating better physical functioning.
The Academy of Acute Care Physical Therapy of the American Physical Therapy Association created Clinical Practice Guidelines (CPG) for a core outcomes set for “initial examination and at hospital milestones” when patients receive physical therapy during hospitalization (Mayer et al, 2025, p3). In addition to the core outcomes set, the CPG recommends the FSS-ICU as one of the “Supplemental measures” for critically ill patients (Mayer et al, 2025, p9).
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FSS-ICU – English Version FSS-ICU – Other Languages Validation Studies Alves GAA, Martinez BP, Lunardi AC. Assessment of the measurement properties of the Brazilian versions of the Functional Status Score for the ICU and the Functional Independence Measure in critically ill patients in the intensive care unit. Rev Bras Ter Intensiva. 2019; 31(4):521-528. Link to PubMed Camus-Molina A, Gonzalez-Seguel F, Castro-Avila A, Leppe J. Construct Validity of the Chilean-Spanish Version of the Functional Status Score for the Intensive Care Unit: A Prospective Observational Study Using Actigraphy in Mechanically Ventilated Patients. Arch Phys Med Rehabil. 2020; 101(11):1914-1921. PubMed Da Silva VZM, Araujo Neto JA, Cipriano Jr G, Pinedo M, Needham DM, Zanni JM, Guimaraes FS. Brazilian version of Functional Status Score for the Intensive Care Unit (FSS-ICU): translation and cross-cultural adaptation. Brazilian Journal of Intensive Care. 2017; 29:34-38. Article | PubMed Do JG, Suh GH, Won YH, Hiser S, Needham DM, Chung CR. Reliability and validity of the Korean version of the functional status score for the ICU after translation and cross-cultural adaptation. Disability and Rehabilitation, 2021; 42(21), 3092–3097. Article | PubMed Gonzalez-Seguel F, Camus-Molina A, Carcamo M, Hiser S, Needham D, Leppe J. Inter-observer reliability of trained physiotherapists on the Functional Status Score for the Intensive Care Unit (FSS-ICU) Chilean-Spanish version. Physiotherapy Theory and Practice. 2022; 38:2, 365-371. Link to PubMed | Link to Article Gonzalez-Seguel F, Camus-Molina A, Leppe J, Hidalgo-Cabalin V, Gutierrez-Panchana T, Needham DM, Guimaraes FS. Chilean version of the Functional Status Score for the Intensive Care Unit: translation and cross-cultural adaptation. Medwave. 2019;19:e7439. Article | PubMed Gonzalez-Seguel F, Corner EJ, Merino-Osorio C. International Classification of Functioning, Disability, and Health Domains of 60 Physical Functioning Measurement Instruments Using During the Adult Intensive Care Unit Stay: A Scoping Review. Physical Therapy. 2019; 99(5):627-640. Article | PubMed Huang M, et al. Functional Status Score for the ICU: An International Clinimetric Analysis of Validity, Responsiveness, and Minimal Important Difference. Crit Care Med. 2016;44(12). Link to PubMed Kahraman BO, Ozsoy I, Kahraman T, Tanriverdi A, Acar S, Ozpelit E, Akdeniz B, Hiser S, Guimaraes FS, Needham DM, Savci S. Turkish translation, cross-cultural adaptation, and assessment of psychometric properties of the Functional Status Score for the Intensive Care Unit. Disability and Rehabilitation, 2019; 44(24), 7528–7534. Article | PubMed Parry SM, et al. Functional outcomes in ICU – what should we be using? – an observational study. Crit Care. 2015;19:127. Link to Article | Link to PubMed Parry SM, Huang M, Needham D. Evaluating physical functioning in critical care: considerations for clinical practice and research. Critical Care. 2017; 21:249. Free full text | PubMed Ragavan VK, et al.The Functional Status Score for the Intensive Care Unit Scale: Is It Reliable in the Intensive Care Unit? Can It Be Used to Determine Discharge Placement? JACPT. 2016;7(3):93-100. Link to Article Thrush A, Steenbergen E. Clinical properties of the 6-clicks and Functional Status Score for the ICU in a hospital in the United Arab Emirates. Archives of Physical Medicine and Rehabilitation. 2022 Dec;103(12):2404-2409. Link to PubMed |Link to Article Tymkew H, Norris T, Arroyo C, Schallom M. The Use of Physical Therapy ICU Assessments to Predict Discharge Home. Crit Care Med. 2020 ;48(9):1312-1318 Article | PubMed Wu, T. T., Su, Q. P., Xiong, J., Hiser, S., Needham, D. M., & Li, H. 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