Objectives A high number of street dealers operate in the Red Light District in
Amsterdam, The Netherlands. To displace the dealers, the Municipality of Amsterdam installed text-based light projections in a street attracting a high number of dealers.
Methods To evaluate the intervention, we did a pre-post analysis of video footage from two CCTV cameras located in the street. In total, we analyzed 765 one-minute segments of footage from before and after the implementation.
Results The implementation was followed by a four percentage point reduction in street dealers. However, the estimated efect shows fragileness with wide confdence intervals and a p-value just below 0.05, and a Bayesian robustness analysis suggests that the intervention was not associated with the outcome.
Conclusions Analyzing CCTV-footage ofers a unique avenue for evaluating small
scale interventions in open-air drug markets. While we observed a decrease in the presence of dealers, the intervention still needs further validation.