Large-scale reductions in speeding and accidents in Canada and Israel: a behavioral ecological perspective.

The team put up big signs at busy city intersections. The signs showed drivers how many people sped the week before.

They tried signs alone first. Later they added warning tickets for speeders. They tracked crashes and speeding across whole cities in Canada and Israel.

Speeding dropped when the signs went up. Crashes fell too. The biggest change came when signs plus warning tickets were used together.

Houten et al. (1983) tested the same idea two years earlier at single stop lights. Their signs also cut speeding, but the 1985 study proved the trick works city-wide.

Sisson et al. (1993) looks like a clash. They posted feedback about drunk driving outside bars and saw no change. The difference: drunk drivers can’t read signs well, so the feedback never hit. Sober commuters in traffic can see and use the sign—hence the crash drop.

Sleiman et al. (2020) pooled 96 workplace feedback studies and still found big gains. The 1985 road signs are an early, outdoor example of that same powerful lever.

You already use feedback charts with clients. This paper says public feedback can shape whole communities. If you consult with cities, schools, or camps, post a simple count of last week’s safe behaviors where everyone walks past. Add a mild consequence for rule breakers if you can. The combo can cut risky acts fast and cheap.