|
Affiliation
|
Bradford School of Optometry and Vision Science, University of Bradford, Bradford, West Yorkshire, BD7 1DP, UK. |
|
Abstract
|
BACKGROUND: Falls sustained when descending stairs are the leading cause of accidental death in older adults. Highly visible edge highlighters/friction strips (often set back from the tread edge) are sometimes used to improve stair safety, but there is no evidence for the usefulness of either.
OBJECTIVE: To determine whether an edge highlighter and its location relative to the tread edge affect foot placement/clearance and accidental foot contacts when descending stairs.
METHOD: Sixteen older adults (mean±1SD age; 71±7years) with normal vision (Experiment 1) and eight young adults (mean±1SD age; 24±4years) with a visual impairment due to simulated age-related cataract (Experiment 2) completed step descent trials during which a high contrast edge highlighter was either not present, placed flush with the tread edge, or set back from the edge by 10mm or 30mm. Foot placement/clearance and the number of accidental foot contacts were compared across conditions.
RESULTS: In experiment 1, a highlighter set back by 30mm led to a reduction in final foot placement (p<0.001) and foot clearance (p<0.001) compared to a highlighter placed flush with the tread edge, and the percentage of foot clearances that were less than 5mm increased from 2% (abutting) to 17% (away30). In experiment 2, a highlighter placed flush with the tread edge led to a decrease in within-subject variability in final foot placement (p=0.004) and horizontal foot clearance (p=0.022), an increase in descent duration (p=0.009), and a decrease in the number of low clearances (<5mm, from 8% to 0) and the number of accidental foot contacts (15% to 3%) when compared to a tread edge with no highlighter present.
CONCLUSIONS: Changes to foot clearance parameters as a result of highlighter presence and position suggest that stairs with high-contrast edge highlighters positioned flush with the tread edge will improve safety on stairs, particularly for those with age-related visual impairment.
Language: en |