Executive summary

In 2019, Transport Scotland’s Scottish Road Research Board commissioned WSP to study the gap between vulnerable road users’ perception of vehicle speeds in comparison to actual speeds on Scotland’s roads.

Following a literature review and pilot study, the project was paused during the most significant portion of the COVID-19 pandemic and resumed in 2022.

This report concludes the project, presenting the findings of the project from 2022-2023 and suggesting the next steps for further research.

Analysis of a household survey of 589 Scottish residents across 13 settlements bisected by a trunk road found that traffic speed, volume, and noise were the most commonly cited barriers to active travel near the trunk road. In respondents’ wider areas, they also cited lighting and crossing times as barriers to active travel.

By using the relative speed estimate – that is, the mathematical difference between estimated speed and recorded speed – as the dependent variable for statistical analysis, this project was able to provide the following further insights:

  • On average, respondents overestimated traffic speeds by 7.5mph.
  • People with a disability that limits their day-to-day mobility or with pets in the household were more likely to overestimate traffic speeds.
  • When we considered factors individually, there was no significant difference between estimation levels across gender, vehicle ownership, children in household, or age.

Taking all of these variables into consideration at the same time through regression modelling, the following demographic and geographic factors appear to have a statistically significant impact on overestimation of traffic speeds:

  • Disabilities affecting mobility
  • Pets and/or children in household
  • Vehicle in the household
  • Length of time at current address
  • Lower traffic volumes and lower actual speeds
  • Narrower roads
  • Commercial settings
  • Barriers between pedestrians and traffic

To further understand the implications of these findings, Transport Scotland could consider conducting field trials of speed indicator devices on trunk road high streets in combination or comparison with other interventions to support residents to estimate speed more accurately and feel safer in the trunk road environment.