Factors related to self-rated health in older adults: a clinical approach using the International Classification of Functioning, Disability, and Health (ICF) model

Key points

1. 01Double-support time during gait was the single best predictor of self-rated health (R2 = 0.50, P = .001), outperforming gait speed and step length
2. 02Higher BMI was associated with lower self-rated health (rs = -0.4, P = .015) and worse gait and balance confidence
3. 03The low BMI group spent significantly less time in double support than the high BMI group (t = -3.8, P = .001)
4. 04Self-rated health is a single-question tool that captures the patient perspective and was associated with multiple ICF domains
5. 05No participant rated their health as poor; 75% rated it good or very good, consistent with community-dwelling samples

How it was conducted

Design

Cross-sectional observational study with bivariate correlations and ordinary least squares regression

Participants

30 community-dwelling adults aged 65-92 years (mean 74.1 years; 18 women, 12 men); all white/Caucasian; recruited in Bangor, Maine

Primary outcome

Self-rated health on a 5-point scale (poor to excellent)

Key measures

Spatiotemporal gait via Zeno Walkway (gait speed, double-support time, step length, cadence), BMI, isokinetic knee extensor strength, ABC-6 balance confidence, Keele Assessment of Participation, NEWS-A neighborhood walkability

Framework

International Classification of Functioning, Disability, and Health (ICF) used to organise variable selection across body structure, activity, participation, and environmental domains

What they found

• Double-support time correlated with self-rated health: rs = -0.6, P < .001 (strongest bivariate association)
• Regression model with double support explained 50% of variance in self-rated health: R2 = 0.50, F(3,26) = 7.3, P = .001; standardised beta = -0.7 (95% CI: -0.2 to -0.1)
• Gait speed correlated with self-rated health: rs = 0.4, P = .05; regression beta = 0.5 (95% CI: 0.01-0.03), P = .011, R2 = 0.3
• Normalised step length correlated with self-rated health: rs = 0.4, P = .05; regression beta = 0.5 (95% CI: 1.8-12.2), P = .011, R2 = 0.3
• BMI correlated with self-rated health: rs = -0.4, P = .015; BMI-only regression model was not significant after controlling for age and education
• Neighborhood hilliness correlated with self-rated health: rs = -0.4, P = .015; regression model not significant after covariates
• Low vs high BMI groups: double-support time t(28) = -3.8, P = .001; gait speed t(28) = 2.2, P = .033; balance confidence difference of 10.8% (ABC-6 total score difference not statistically significant: t(28) = 1.5, P = .1)
• Reaching-overhead balance confidence item (ABC-6 item 1) correlated with SRH: rs = 0.5, P = .011; with BMI: rs = -0.7, P < .001; with double-support time: rs = -0.7, P < .001; with step length: rs = 0.6, P < .001; with gait speed: rs = 0.5, P = .005

Limitations

• Small convenience sample of 30 predominantly healthy, white, community-dwelling older adults limits generalisability
• Sample recruited from universities and desirable retirement communities, reducing variability in environmental, participation, and personal factors
• Important correlates of self-rated health such as physical activity, nutrition, depression, and comorbidities were not assessed
• Isokinetic strength showed no meaningful association with self-rated health; functional strength measures (e.g., sit-to-stand) were not tested and may be more clinically relevant

Why it matters

For patients

Older adults who walk more fluidly and spend less time with both feet on the ground tend to rate their health more positively, suggesting that improving walking ability may support a sense of overall wellbeing.

For clinicians

Double-support time during gait is a quick, technology-assisted measure that predicts self-rated health better than gait speed alone, and together with BMI it can provide a richer picture of a geriatric patient's functional health status.

For readers

This preliminary ICF-framed study supports including self-rated health alongside gait analysis and BMI in geriatric physical therapy assessments, though replication in larger and more diverse samples is needed before strong clinical recommendations can be made.