Mandatory hi-vis had no influence on number of cyclists involved in collisions according to Italian study

An Italian study has taken a look at “the role of conspicuity in preventing bicycle–motorized vehicle collisions.” Put another way, researchers looked at whether legislation demanding that cyclists wear high-vis had any impact on safety. They found that it did not.

BikeBiz reports that data on the monthly number of vehicles involved in road crashes during the period 2001–2015 were obtained from the Italian National Institute of Statistics.

Results revealed that legislation demanding that cyclists wear high-visibility clothing did not influence the total number of cyclists involved in road collisions and nor did it affect the number of collisions involving cyclists as a proportion of all vehicle collisions.

“The introduction of the legislation did not produce immediate effects, nor did it have any effects over time,” concluded the researchers.

They did however concede that they had not taken account of the extent to which hi-vis laws were being adhered to by cyclists, writing: “Lack of knowledge on how the law was introduced, the degree of enforcement by the police, and behavioural changes in response to the law makes it difficult to attribute the lack of effect on bicycle crashes.”

A study carried out last year by the Nottingham University Hospitals NHS Trust and Nottingham University found “increased odds of a collision crash” among cyclists who wear reflective clothing.

The researchers suggested that riders who believe they are more conspicuous may adopt more exposed positions on the road, before going on to point out that the results “should be treated with caution” as they were based on only 76 accidents.

In contrast, a larger study in Denmark, involving nearly 7,000 cyclists, found cyclists suffered 47 per cent fewer accidents causing injuries if a bright yellow jacket was worn.

2013 research from the University of Bath and Brunel University found that no matter what clothing a cyclist wears, around 1-2 per cent of drivers will pass dangerously close when overtaking.