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Functional Ability Transfer Index (or Functional Capacity Assessment Index)

Published: August 9, 2026Updated: August 17, 2026

This test evaluates how well your body can perform physical tasks, often used to assess overall health, recovery from illness, or functional limitations.

Quick summary

["Understanding your body’s ability to function helps guide treatment and daily activities."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 17, 2026Editorial policy

Key facts at a glance

LOINC
57246-1
Short code
TRANSFERRINGFUNCTIONALABILITY
Synonyms
—
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Ref low
200
Ref high
350
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
cms-assessment
CPT
84466
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

What This Test Measures

This test measures how efficiently your body uses energy and resources during physical activity. It combines data from blood tests, metabolic studies, and functional testing to create an overall index of your functional capacity. This may include measurements of oxygen use, heart function, muscle strength, and endurance.

Why It’s Done

Doctors may order this test if you have chronic conditions like heart disease, lung problems, or mobility issues, or if you’re recovering from surgery, illness, or injury. It helps determine how well you can perform daily tasks and plan care tailored to your needs.

Common Uses in Healthcare

Results are used to assess recovery progress, adjust treatments (like physical therapy or medication), or identify areas needing improvement. It’s also helpful for planning safe activities and preventing complications.

How the Test Works

The test involves multiple steps: blood samples may be taken to check metabolic markers, and you’ll perform physical tasks (like walking or lifting) while connected to monitoring devices. These measurements are analyzed to create a personalized functional ability index.

Reference range

NCBI: Transferrin 200-350 mg/dLN/A

Specimen: serum

Fasting for 12 hours preferred. Iron supplements should be stopped 24 hours before if possible.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance

Frequently asked questions

How does this test differ from a regular physical exam?
Unlike a physical exam alone, this test provides a detailed, measurable snapshot of how your body functions during activity. It combines lab results with real-time performance data to give a more precise picture of your abilities and limitations.
What if my results are lower than expected?
Lower results may indicate areas where your body struggles to perform tasks efficiently. This could signal the need for medical interventions, such as physical therapy, medication adjustments, or lifestyle changes to improve function.
Can this test be done at home?
No, this test requires specialized equipment and professional supervision. It’s typically performed in a clinical setting, such as a hospital or rehabilitation facility, to ensure accuracy and safety.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 17, 2026. · Read our editorial policy