Aim: To investigate the hypothesis that wearing socks over shoes improves traction on icy footpaths.
Methods: Randomised controlled trial involving 30 pedestrians (median age 21 years, range 18-70) travelling in a downhill direction on icy public footpaths at two sites in Dunedin, New Zealand.
Intervention: different coloured socks applied over normal footwear or usual practice (unadulterated footwear).
Primary outcome: difference in mean self-reported slipperiness on a 5-point scale.
Secondary outcomes: falls, observer-rated slipperiness, observer-rated confidence, time to descend study slope.
Results: Two-thirds of participants (65%) had previously fallen on ice. Wearing socks over normal footwear was associated with a statistically significant improvement in traction; the difference in mean self-reported slipperiness scores between the control (n=15) and intervention (n=14) groups was 1.3 (95%CI: 0.4-2.3). Agreement between self-rated and observer-rated slipperiness was high (r=0.70). A higher proportion of the intervention group (71% vs 53%) appeared confident. One member of the control group fell. There was no evidence of risk compensation in the intervention group (difference in mean descent times 1.9 seconds, 95%CI: -6.1-10.0). The only adverse events were short periods of indignity for some members of the intervention group.
Conclusion: Wearing socks over shoes appears to be an effective and inexpensive method to reduce the likelihood of slipping on icy footpaths.