Table 1 Characteristics of multivariate frailty indices used in previous frailty and falls prevention studies and in this study

Country

UK

China

Canada

England

England

Data source

Electronic health records

Cohort survey

Cohort survey

Cohort survey

Cohort survey

Total # of items

36

33²

34

40

52

Mean (SD)

Men: 0.13 (0.09)

Women: 0.15 (0.10)

Men: 0.11 (0.10)

Women: 0.14 (0.12)

Women only: 0.24 (0.13)

Both sex: 0.16 (0.11)

Men: 0.11 (0.09)

Women: 0.13 (0.10)

Severity categories

[Fit] 0-0.12 (50%)

[Mild] > 0.12–0.24 (35%)

[Moderate] > 0.24–0.36 (12%)

[Severe] > 0.36 (3%)

[1] 0-0.03

[2] > 0.03–0.10

[3] > 0.10–0.20

[4] > 0.20–0.50

[5] > 0.50

[Robust] 0-0.20 (43.9%)

[Prefrail] > 0.20–0.35 (34.1%)

[Frail] > 0.35 (22.1%)

[Non-frail] 0-<0.25 (81.5%)

[Frail] > = 0.25 (18.5%)

[Fit] 0-0.10 (50%)

[Mild] > 0.10–0.23 (35%)

[Moderate] > 0.23–0.37 (12%)

[Severe] > 0.37 (3%)

Component items

Chronic diseases

(17) Anemia; Arthritis; AF; CBVD; CKD; Diabetes; Heart failure; Heart valve disease; Hypertension; Hypotension; IHD; Osteoporosis; PD; PVD; RD; Thyroid disease; Urinary system disease

(8) Arthritis; Cataract; CHD; Glaucoma; Hypertension; Stroke; Thyroid disease; TIA

(13) Cancer; Celiac disease; Chronic bronchitis; Crohn’s disease; Diabetes; Heart disease; High cholesterol; Hypertension; Multiple sclerosis; Osteoarthritis; PD; RA; Stroke

(15) Blood disease; Cancer; Digestive disease; Ear disease; Endocrine disease; Eye disease; Genitourinary disease; Heart disease; Infectious disease; Mental disease; MSKD; Nervous disease; RD; Skin disease; Other disease

(20) Angina; Arrhythmia; Arthritis; Asthma; Cancer; Cataract; Depression; Diabetes; DED; DKD; Glaucoma; Heart attack; Heart disease– other; Heart murmur; Hypertension; High cholesterol; Lung disease; MD; Osteoporosis; Stroke

Sensory/physical impairments and geriatric syndromes

(12) Hearing impairment; Visual impairment; Dizziness; Dyspnea; Falls; Foot problems; Fragility fractures; Peptic ulcer; Skin ulcer; Sleep disturbance; UI; Weight loss and anorexia

(5) Hearing problem; Use a hearing aid; Use a walking aid; Tremor; UI

(1) Unintentional weight loss

(2) Use a walking aid; Balance problems

(8) Seeing difficulties; Hearing difficulties; Slow walking speed;^3,4 Balance problems;⁴ Weak grip strength;^3,4 Weak leg strength;⁴ UI; Significant weight loss^3,4

Cognitive impairment

(1) Memory and cognitive problems

(1) MMSE < 15

(1) Composite measure of cognitive problems across 4 tests of memory, mental speed and numeracy

Subjective symptoms and health status

(5) Lack of energy; Felt less useful; Don’t feel a lot of fun in life; Don’t feel very happy; Feel nothing to do

(6) Feels full of life; Has a lot of energy; Feels worn out; Feels tired; Self-rated health; Self-rated pain

(6) Feeling calm; Have a lot of energy; Feeling low; Social activity interfered by physical and emotional health; Self-rated health; Normal work interfered by pain

(4) Self-reported exhaustion;³ Self-rated health; Self-rated pain; Self-reported long-standing illness

Lifestyle risk factors

(2) Obesity (BMI > = 30); Low physical activity

(2) Low physical activity;³ Obesity

Activity limitation

(3) Any activity limitation; Housebound; Mobility and transfer problems

(14) ADL & IADL limitations

(12) ADL limitations

(14) ADL & IADL limitations

(15) ADL & IADL limitations

Healthcare contact

(2) Polypharmacy (5 + medications); Requirement for care

(2) Polypharmacy (5 + medications); Frequency of healthcare visit in past year

(1) Polypharmacy (6 + medications)

(1) Polypharmacy (5 + medications)

Social

(1) Social vulnerability

(1) Living alone