Faller Classification Ability of Self-Administered Balance and Gait Assessments Conducted Using a Guiding Smartphone Application

Introduction

This study aimed to evaluate the effectiveness of self-administered balance and gait assessments, conducted using a guiding smartphone application, in distinguishing recurrent fallers from non-fallers.

Method

Thirty-nine older adults (mean age=71.1±5.7 years; recurrent fallers=17, non-fallers=22) independently completed 30-second feet-together and tandem standing tests, as well as a 6-minute walking assessment, using the smartphone application. Participants performed the tests twice in the laboratory and twice at home, wearing the smartphone on their waist during all assessments to record acceleration. Standing balance was evaluated by calculating displacements in anteroposterior and mediolateral directions and path length. Gait stability was evaluated through sway and regularity metrics.

Test–retest reliability was assessed using intraclass correlation coefficients (ICC). Variables with at least moderate reliability were used to develop multivariate models for classifying recurrent fallers. The discriminatory ability of the smartphone-based models, gait speed, and the timed-up-and-go (TUG) test was evaluated using the area under the receiver operating characteristic curve (AUC).

Results

Test–retest reliability ranged from poor to good for balance outcomes (ICC=0.00–0.80) and from good to excellent for walking-related variables (ICC=0.73–0.94). Path length showed consistent moderate-to-good reliability during feet-together tests in both laboratory and home settings and during tandem standing in the laboratory (ICC=0.66–0.73). All tandem standing outcomes tested at home demonstrated poor reliability (ICC≤0.18).

Multivariate models based solely on walking-related variables achieved AUCs of 0.82 and 0.89 for laboratory and home assessments, respectively. The AUC for the home assessment further improved to 0.92 when path length from the feet-together test was included. Gait speed and TUG produced lower AUCs of 0.73 and 0.69, respectively.

Conclusion(s)

Self-assessment of standing balance and gait stability using a guiding smartphone application is feasible for older adults and provides better discrimination of recurrent fallers than conventional tests. Home-based assessments outperformed laboratory assessments, warranting larger-scale studies.