Frailty Index
Quantify frailty by counting deficits across health domains. FI = deficits present ÷ total assessed. Higher = more frail.
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FI <0.08 robust FI 0.25+ frail Deficit accumulation model
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Why: Frailty predicts falls, hospitalization, and mortality. Early identification enables targeted interventions.
How: Count deficits (chronic conditions, ADL/IADL impairments, physical limitations). FI = proportion present.
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Robust Elderly (70F)
Active elderly woman with minimal health issues
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Pre-Frail (76M)
Elderly man with early signs of frailty
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Mild Frailty (80F)
Woman with mild frailty, needs some assistance
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Moderate Frailty (84M)
Man with moderate frailty and multiple deficits
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Severe Frailty (88F)
Nursing home resident with severe frailty
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Deficit Assessment
Chronic Conditions
Activities of Daily Living (ADL)
Instrumental ADL (IADL)
Physical Performance
Other Health Deficits
For informational purposes only — not medical advice. Consult a healthcare professional before acting on results.
🏥 Health Facts
FI 0-0.08: robust
— Geriatric medicine
FI 0.25+ indicates frailty
— Validation studies
What is the Frailty Index?
The Frailty Index (FI) is a clinical tool that quantifies frailty by measuring the proportion of potential health deficits that are present in an individual. Developed by Dr. Kenneth Rockwood and colleagues, it is based on the "deficit accumulation" model of aging - the idea that the more health problems a person accumulates, the more frail they become.
The FI can include 30 or more deficits spanning chronic diseases, functional impairments, cognitive status, and other health measures. The index is calculated as a proportion: number of deficits present divided by total deficits assessed. Higher values indicate greater frailty.
<0.15
Robust
0.15-0.24
Pre-Frail
0.25-0.34
Mild
0.35-0.44
Moderate
0.45-0.54
Severe
0.55+
Very Severe
How to Calculate the Frailty Index
- Define Deficits: Identify health deficits from multiple domains (diseases, function, cognition)
- Assess Each Deficit: Determine presence or absence of each deficit
- Count Present Deficits: Sum the number of deficits present
- Calculate Index: Divide present deficits by total deficits assessed
- Classify Frailty: Use established cutoffs to determine frailty level
Frailty Index Formula
FI = Number of Deficits Present / Total Deficits Assessed
Example: 12 deficits / 38 assessed = 0.32 (Mild Frailty)
When to Use the Frailty Index
Clinical Applications
- • Comprehensive geriatric assessment
- • Pre-operative risk stratification
- • Care planning and goal setting
- • Monitoring changes over time
- • Research and epidemiology
- • Identifying intervention targets
Advantages of the FI
- • Continuous rather than categorical measure
- • More sensitive to change than phenotype models
- • Can be derived from existing health data
- • Applicable across diverse populations
- • Predicts mortality better than age alone
Evidence-Based Frailty Interventions
Physical Interventions
- • Progressive resistance training 2-3x/week
- • Multicomponent exercise programs
- • Balance and gait training
- • Physical therapy referral
- • Otago exercise program
- • Tai Chi for balance
Nutritional Interventions
- • Protein supplementation (1.2-1.5 g/kg/day)
- • Vitamin D optimization (>30 ng/mL)
- • Mediterranean diet pattern
- • Address malnutrition/sarcopenia
- • ONS for weight loss
- • Dietitian referral
Medical Management
- • Comprehensive medication review
- • Deprescribing where appropriate
- • Optimize chronic disease management
- • Screen for depression/cognitive decline
- • Manage pain effectively
- • Immunizations up to date
Comprehensive Geriatric Assessment (CGA)
For patients with FI >0.25, consider referral for Comprehensive Geriatric Assessment. CGA has been shown to reduce mortality, increase likelihood of living at home, and improve function in frail older adults compared to usual care.
Prognostic Implications by FI Category
FI <0.10: Robust/Non-frail
5-year mortality risk: ~8%
Hospitalization risk: Low
Recommendations: Preventive care, lifestyle counseling
FI 0.10-0.24: Pre-frail
5-year mortality risk: ~20%
Hospitalization risk: Moderate
Recommendations: Targeted interventions, exercise, nutrition
FI 0.25-0.44: Mildly/Moderately Frail
5-year mortality risk: ~35-50%
Hospitalization risk: High
Recommendations: CGA, multimodal interventions, care planning
FI ≥0.45: Severely Frail
5-year mortality risk: >65%
Hospitalization risk: Very High
Recommendations: Goals of care discussion, palliative approach
Frailty Index vs Other Frailty Measures
| Feature | Frailty Index | Fried Phenotype | Clinical Frailty Scale |
|---|---|---|---|
| Approach | Deficit accumulation | Physical phenotype | Clinical judgment |
| Number of Items | 30-70+ | 5 | 1 (9-point scale) |
| Administration Time | 15-30 min | 10-15 min | 1-2 min |
| Equipment Needed | None/minimal | Dynamometer, stopwatch | None |
| Best For | Research, detailed assessment | Standardized measurement | Quick clinical screening |
Clinical Decision Support by Setting
Preoperative Setting
- • FI >0.25: Consider non-surgical alternatives
- • FI >0.35: High-risk for postop complications
- • Prehabilitation may reduce frailty before surgery
- • Discuss realistic expectations with patient/family
- • Consider geriatric co-management
Oncology Setting
- • FI helps guide treatment intensity selection
- • Frail patients have higher chemo toxicity
- • May benefit from geriatric oncology assessment
- • Consider supportive care pathways
- • Discuss goals of care early
Emergency Department
- • Frailty predicts ED revisits and admission
- • Consider observation vs admission
- • Coordinate discharge planning early
- • Identify for community support services
- • Document baseline function
Primary Care
- • Annual frailty screening for 65+
- • Track FI change over time
- • Early intervention for pre-frailty
- • Coordinate multidisciplinary care
- • Advanced care planning discussions
Modifiable Risk Factors for Frailty
Sarcopenia
Address with protein + exercise
Malnutrition
Nutritional assessment + ONS
Sedentarism
Exercise prescription
Depression
Screen + treat appropriately
Polypharmacy
Medication review + deprescribe
Social Isolation
Social worker referral
Vitamin D Deficiency
Supplement to >30 ng/mL
Chronic Pain
Pain management optimization
Documentation & Communication
Required Documentation
- • Date of assessment and assessor credentials
- • Total number of deficits assessed
- • Total number of deficits present
- • Calculated Frailty Index score
- • Frailty category classification
- • Specific deficits identified by domain
- • Comparison to previous assessment if available
Communication Tips
- • Use "frailty" with sensitivity - avoid stigmatizing
- • Emphasize frailty as potentially modifiable
- • Focus on functional goals rather than deficits
- • Involve patient and family in goal-setting
- • Discuss realistic expectations for intervention
- • Address advance care planning when appropriate
Reassessment Schedule
Reassess the Frailty Index: annually for stable patients, every 3-6 months for those with interventions in progress, and whenever there is a significant change in health status or new hospitalization. Track changes over time to assess intervention effectiveness.
Key References
- 1. Rockwood K, Mitnitski A. Frailty in relation to the accumulation of deficits. J Gerontol A Biol Sci Med Sci. 2007;62(7):722-727.
- 2. Searle SD, Mitnitski A, Gahbauer EA, Gill TM, Rockwood K. A standard procedure for creating a frailty index. BMC Geriatr. 2008;8:24.
- 3. Clegg A, Young J, Iliffe S, Rikkert MO, Rockwood K. Frailty in elderly people. Lancet. 2013;381(9868):752-762.
- 4. Fried LP, Tangen CM, Walston J, et al. Frailty in older adults: evidence for a phenotype. J Gerontol A Biol Sci Med Sci. 2001;56(3):M146-M156.
- 5. Dent E, Martin FC, Bergman H, Woo J, Romero-Ortuno R, Walston JD. Management of frailty: opportunities, challenges, and future directions. Lancet. 2019;394(10206):1376-1386.
- 6. Hoogendijk EO, Afilalo J, Ensrud KE, Kowal P, Onder G, Fried LP. Frailty: implications for clinical practice and public health. Lancet. 2019;394(10206):1365-1375.
- 7. Theou O, Rockwood K. Comparison and clinical applications of the Frailty Phenotype and Frailty Index approaches. Interdiscip Top Gerontol Geriatr. 2015;41:74-84.
- 8. Church S, Rogers E, Rockwood K, Theou O. A scoping review of the Clinical Frailty Scale. BMC Geriatr. 2020;20(1):393.
- 9. Kojima G. Frailty as a predictor of nursing home placement among community-dwelling older adults: A systematic review and meta-analysis. J Geriatr Phys Ther. 2018;41(1):42-48.
- 10. Song X, Mitnitski A, Rockwood K. Prevalence and 10-year outcomes of frailty in older adults in relation to deficit accumulation. J Am Geriatr Soc. 2010;58(4):681-687.
- 11. Rockwood K, Song X, MacKnight C, et al. A global clinical measure of fitness and frailty in elderly people. CMAJ. 2005;173(5):489-495.
- 12. Kojima G, Iliffe S, Walters K. Frailty index as a predictor of mortality: a systematic review and meta-analysis. Age Ageing. 2018;47(2):193-200.
- 13. Morley JE, Vellas B, van Kan GA, et al. Frailty consensus: a call to action. J Am Med Dir Assoc. 2013;14(6):392-397.
- 14. Blodgett JM, Theou O, Kirkland S, Andreou P, Rockwood K. The association between sedentary behaviour, moderate-vigorous physical activity and frailty in NHANES cohorts. Maturitas. 2015;80(2):187-191.
- 15. Walston J, Buta B, Xue QL. Frailty Screening and Interventions: Considerations for Clinical Practice. Clin Geriatr Med. 2018;34(1):25-38.
- 16. Puts MTE, Toubasi S, Andrew MK, et al. Interventions to prevent or reduce the level of frailty in community-dwelling older adults: a scoping review of the literature and international policies. Age Ageing. 2017;46(3):383-392.
- 17. Kojima G, Taniguchi Y, Iliffe S, Walters K. Frailty as a Predictor of Alzheimer Disease, Vascular Dementia, and All Dementia Among Community-Dwelling Older People. J Am Med Dir Assoc. 2016;17(10):881-888.
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