Functional Assessment

Overview and Description

Functional assessments have evolved into a crucial component of the comprehensive rehabilitation medicine evaluation. The descriptions of improvements in function, a practice that has been consistently performed since the development of rehabilitation medicine after World War II, have gained significant importance. Unfortunately, the methods previously used lacked the consistency required to accurately study rehabilitation outcomes.¹

Functional assessment is a comprehensive process that measures an individual’s level of function and ability to perform specific tasks on a safe and dependable basis over a defined period. A detailed assessment includes a pertinent clinical history; a neurologic and musculoskeletal evaluation, a physical effort determination, and a comprehensive evaluation of behaviors that might impact physical performance.² These assessments are not just valid, reliable, and reproducible, but also cover a wide range of aspects, making them thorough and comprehensive.

From a research perspective, functional assessments serve as vital evidence for the development, enhancement, and validation of various evidence-based treatments. In the clinical environment, these tools are widely used to establish rehabilitation goals, devise specific therapeutic interventions, and monitor clinical changes.³

In 2001, the World Health Organization (WHO) endorsed an international standard to describe and measure health and disability through an instrument called the International Classification of Functioning, Disability and Health (ICF). The ICF is a manual that serves as framework that seeks to measure health and disability in populations and individuals. (MC1) Its main goal is to create a standard language to measure and classify disability in a bio-psycho-social model, distancing from relating disability to a health condition, but to a functional problem. Its uses vary from clinical to policy design, but when used in the clinical setting, its main use involves outcome evaluation.⁴ There are some challenges associated to its use, which hinders worldwide implementation.

In 2014, the trajectory of functional assessments shifted significantly with the signing of the Improving Medicare Post-Acute Care Transformation Act of 2014 (the IMPACT Act). This legislation aimed to connect baseline assessment findings to functional outcomes, mandating Long-Term Care Hospitals (LTCHs), Skilled Nursing Facilities (SNFs), Home Health Agencies (HHAs), and Inpatient Rehabilitation Facilities (IRFs) to report and submit standardized patient assessment data. This data exchange facilitated the sharing of information among providers on specific functional domains, including functional status, cognitive function, and mental status, among others. The ultimate goal was to enhance rehabilitation outcomes through shared decision making, care coordination, and improved discharge planning.⁵

Relevance to Clinical Practice

The field of Rehabilitation Medicine has a broad scope of practice and includes a variety of conditions such as neurological (stroke, TBI, neurodegenerative), musculoskeletal (joint pain, tendinopathies, ligamentous injuries, balance dysfunction), pain syndromes, medical (deconditioning, cardiopulmonary), rheumatologic (Rheumatoid Arthritis, Osteoarthritis, Connective Tissue Disorders), and others.  Functional assessment tools have the capability to establish a baseline measurement, such as pain level, function, range of motion (ROM), etc., for the purpose of quantifying and tracking a patient’s progress over time. This endeavor is aimed at bolstering evidence-based practice and fostering the delivery of high-quality care. Thus, functional assessments can complement the clinical evaluation and guide clinicians’ treatment plans and targeted interventions.

Commonly used assessments vary by population (pediatrics versus adults), activity to be measured, condition or etiology, type of impairment, functional approach, among others. Interrater reliability may vary by the clinician’s ability in managing the tool.

Activities of daily living (Table 1A) measures the performance of basic functional skills required to care for oneself independently. They measure basic daily activities (eating, grooming, bathing, dressing, continence) mobility (gait, transfers) and cognition. Instrumental activities of daily living may also include tasks such as transportation, finances, cooking, and medical management. Examples of some of these instruments include:⁶ 

• Barthel Index (Table 1A)
• Patient specific Functional Scale (Table 1A)
• Canadian Occupational Performance Measure
• Lawton’s Instrumental Activities of Daily Living among others
• Katz Index of Independence on ADL
• Bristol Activities of living scale
• Frenchay Activity Index
• Functional Independence Measure (FIM) (Table 1A, 1B)
• GG Functional Abilities and Goal⁷(Table 2)
• Functional Independence Measure for Children (WeeFIM)⁸
• WHO International Classification of Functioning, Disability, and Health (ICF) (Table 3) ⁹
• International Classification of Functioning, Disability and Health for Children and Youth (ICF-CY)

Table 1A: Activities of Daily Living Scales

Table 1B Functional Independence Measure (FIM) Levels

Table 2: GG Functional Abilities and Goals

Table 3: WHO International Classification of Functioning, Disability, and Health (ICF) form

Quality of life and community re-integration are pivotal rehabilitation goals (Table 4). Additionally, some of these instruments evaluate the effects of executive function deficits on everyday functioning through real world task. Examples include⁶

• Standardized Form-36
• WHO International Classification of Functioning, Disability, and Health (ICF) (Table 3)
• Community Integration Questionnaire
• Reintegration to Normal Living Index
• The Multiple Errands Test.
• Quality of life after TBI(QOLIBRI)
• WHOQOL-100(World Health Organization Quality of life-100)

Table 4: Quality of Life and Community Re-integration Assessment Tools

Palliative Care assessment (Table 5) contains tools intended to measure aspects such as fatigue, functional performance, quality of life in severely ill/cancer and end of life patients. Examples are

• Toolkit of Instruments to Measure End-of-Life Care
• Edmonton Functional Assessment Tool
• Palliative Performance Scale
• Fatigue scale
• Missouta-VITAS Quality of Life Index
• Karnosfky Performance Scale

Table 5: Palliative Care Assessment Tools

Pediatric scales (Table 6)^{8,10,11,12,13,14} are numerous and are usually standardized according to age groups, type of diagnosis, and specific type of functional ability, among some. Areas of assessment include:

• Developmental milestones
• Growth
• Motor skills
• Cognition skills
• Learning and self-help skills
• Communication skills
• Social/Emotional skills

Many pediatric assessment tests require training, certification, and a license, adding a cost to the clinician’s practice. These tests may require extended time to complete an evaluation given the significant number of activities/items that need to be observed; the patient’s ability to cooperate with testing is another variable to consider in the assessment time.

Table 6: Pediatric Assessment Tools

Pain functional assessments (Table 7) assist in evaluation of the severity of pain, how effective treatment interventions have been, and the presence of associated psycho-emotional/behavioral components. Examples include:^6,15,16

• Visual Analog Scale
• The Mc Gill Pain Questionnaire
• Pain Disability questionnaire

 Table 7: Pain functional assessments

Work-Related Injuries (Table 8) are standardized functional assessment tools that globally evaluates functional tolerance (based on a medical condition) that is safe for the worker to perform. Examples of these are⁶

• Functional Capacity Evaluation
• Targeted Functional Assessment

Table 8: Work Related Injuries Functional Assessment

Aerobic/Functional Capacity (Table 9) assessment reflects the ability to perform activities of daily living that require sustained aerobic metabolism. A comprehensive assessment of aerobic capacity allows for assessing baseline status, track improvements and identify any limiting factor that will assist in providing a safe and appropriate intervention. Examples include⁶

• 6 Minute Walk Test, Shuttle Walk Test, Step Test.
• Maximal Oxygen Uptake- VO2 Max, VO2 Peak-Aerobic Capacity.
• 10 meter walk test
• 20 meter shuttle run
• Physiological Cost Index

Table 9: Aerobic/Functional Capacity Measurements

• Balance evaluation (Table 10) has the primary purpose of identifying problems in ambulation to predict risk of a fall, determine the underlying cause of the balance dysfunction and to determine if a treatment is required or has been effective. Nowadays, with the advances in technology, computerized predictions can be performed. Examples of standard tests and technologic assessments include⁶
  • Functional Reach
  • Multi-directional reach test
  • Get up and Go test
  • Timed up and go test
  • Berg Balance test
  • Performance Oriented Mobility Assessment (POMA)
  • History of Falls Questionnaire and Functional Gait Assessment
  • Start execution Balance test
  • Nintendo Wii Balance Board
  • Force plate
  • Posturomed device

Table 10: Balance assessment scales

Cognition (Table 11) evaluation includes memory, attention, language, perception, orientation, learning capacity and overall executive functioning. Computerized tests available promote a more standardized administration of the instruments and ease for interpretation. Some examples include^6,17

• The Glasgow Coma Scale
• Mini Mental Status Exam (MMSE)
• Mini-Addenbrooke’s Cognitive Examination (MACE)
• Brief Cognitive Assessment tool (BCAT)
• Brief Evaluation of Executive Function
• IQCODE
• SLUMS
• Computerized assessment of mild cognitive impairment (CAMCI)
• Montreal Cognitive Assessment (MoCA) *App available
• Neuropsychological batteries
• Glasgow Outcome Scale among others

Table 11: Cognitive

There are other tools designed specifically for certain medical conditions (Table 12) such as⁶

• Stroke
  • NIH Stroke Scale
  • Fugl-Meyer Assessment of Motor Recovery
  • Stroke Impact Scale, and the
  • Bordeaux Verbal Communication Scale
• Traumatic Brain Injury
  • Rancho Los Amigos Scale
  • Agitated Behavior Scale
  • Neurobehavioral Rating Scale-revised
  • Comma Recovery Scale
  • Galveston Orientation Amnesia Test/Orientation-log
  • Dizziness Handicap Inventory, and the
  • Mayo Portland Adaptability questionnaire

Table 12: Stroke and Traumatic Brain Injury

• Musculoskeletal (Table13)^18,19
  • Oswestry Disability Index
  • Western Ontario and McMaster Universities Arthritis Index (WOMAC)
  • Short Musculoskeletal Function Assessment (SMFA)

Table 13: Musculoskeletal

The decision as to which tool to use depends on the patient’s condition, his/her goals, current stage of recovery at which the assessment is being used, the therapist’s training, as well as any restrictions/preferences from the facility where the assessment is taking place.²⁰ When choosing a Functional assessment tool, it is important to understand the sensitivity and specificity of the instrument. Many assessment tools are available through the web and are free of cost. Others might require the purchase of a license to administer prior to its use. In addition, some instruments require training and/or certification, while others do not. It is imperative that the functional assessment evaluator is familiar with the instrument being administered to promote maximal interrater reliability.

Cutting Edge/Unique Concepts/Emerging Issues

Functional assessments are an essential component in rehabilitation medicine assisting with quality assurance, ongoing quality improvement, cost/benefit analysis, education, and research.²¹ Challenges emerge with the interpretation of the data obtained from these instruments and its application on real life situations.

The advancement of technology has brought the possibility to perform functional assessments in new ways, therefore research is being developed to design new functional assessment tools that might provide accurate, valid, reliable, and tangible data.²²  

Virtual care has served as an important mechanism to conduct evaluations, initially because of social distancing and social restrictions during the pandemic, but now as a tool to improve access to remote areas. Targeted methods and approaches have continued to evolve to provide distant interventions and improve patient satisfaction.²³ 

In addition to this, third-party payers have been shaping how services are provided and what outcomes are to be expected.

Finally, recent advances in artificial intelligence technology, may play an important role in facilitating or assisting in the selection of functional assessment tools based on the relevance to the area being assessed. They might also play a role in monitoring patient outcomes through the use of advance data analysis, to improve decision making and optimize interventions. While there is potential for this emerging technology, ethical and fair incorporation in the healthcare systems still needs to be assured.

Gaps in Knowledge/Evidence Base

Gaps are observed in the use of functional assessment tools such as errors and/or bias as information is being conveyed. There is a need for uniformity in assessment tools that permit consistent assessment of disability across treatment sites, across disciplines and geographic locations. Accurate completion of the different instruments is imperative, and this accuracy not only affects the interrater reliability, but the ability of comparing later test results in the same patient upon completing rehabilitation goals. On the other hand, it has been proposed that some functional assessment tools may not provide an objective or accurate account of the patient’s status.

The assessment of any patient with a functional impairment regardless of the etiology should try to quantify such impairment taking into consideration physical, cognitive, behavioral, structural, environmental, and social barriers. It is important to note the complexity of the population due to the multiple subspecialties within the field, such as spinal cord injury, brain injury, palliative care, pediatric, pain management, sport medicine, cardiopulmonary rehabilitation. This diversity calls for a complex, detailed approach with a wide range of required skills and knowledge unique to those areas and with the primary goal of restoring function as well as independence. Standard components of a physiatrist history include chief complaint, history of present illness, allergies, medications, review of system, past/family/psychosocial history, functional history (at home, community, work current and prior to the illness). Emphasis on  motor skills(bed mobility, transitional mobility, ambulation, coordination, balance), activity of daily living(bathing, dressing, grooming, toileting, feeding),  cognition (alertness, orientation, memory, ability to encode new information, communication, etc.), vocational (current, past and future) and use of assistive devices/technology.²⁴ Comprehensive functional assessment evaluations must reflect appropriate medical record documentation that justify the need for the rehabilitation services and evidence the improvement during those interventions.

Evidence based research supporting functional assessments remains limited and many research study sample sizes are small. However, in recent years the use of these tools has led to development, improvement, and approval of rehabilitation treatment modalities and third payer recognition.²⁵ A national/international agreement is necessary to fulfill a uniform assessment of disability across treatment sites, disciplines, and geography. There are still gaps in understanding how a functional assessment can be uniformly applied to different sociodemographic conditions, race, ethnicity, and cultural differences.

References

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Original Version of the Topic

Isabel Borras-Fernandez, MD, Nataly Montes-Chinea MD, Brenda Castillo, MD, Maricarmen Cruz, MD. Functional Assessment. 5/2/2016

Previous Revision(s) of the Topic

Isabel Borras-Fernandez, MD, Maricarmen Cruz, MD, Francisco J. Irizarry-Rivera, MD. Functional Assessment. 11/17/2021

Author Disclosure

Isabel Borras-Fernandez, MD
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Maricarmen Cruz-Jimenez, MD
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David Soto-Quijano, MD
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Edgar Perez-Curet, MD
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Asdrubal Rivera-Dones, MD
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Anna Blanco-Cintron, MD
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Brendaliz Diaz-Guevara, PsyD
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