Cluster analysis of the spatial distribution of pedestrian deaths and injuries by parishes in Kampala city, Uganda

Abstract

Studies on pedestrian deaths and injuries at the urban level in Africa mostly provide overall aggregated figures and do not examine variation in the sub-urban units. Using cluster analysis, this study sought to determine if the observed pattern in the distribution of pedestrian injuries and deaths among parishes in Kampala city is significant. Pedestrian crash data from 2015 to 2019 were collected from the Uganda Traffic Police database. Serious and fatal pedestrian injury rates were mapped by parish using ArcMap and cluster analyses conducted. Results from spatial autocorrelation (Moran’s Index of 0.18 and 0.17 for fatal and serious injury rates respectively) showed that the distributions were clustered within parishes crossed by highways and located in the inner city respectively. Z-scores of 3.32 (p < 0.01) for serious injury rates and 3.71 (p < 0.01) for fatal injury rates indicated that the clustering was not random. This study’s main contribution was providing a detailed spatial distribution of pedestrian fatal and serious injury rates for Kampala; a city in a low developing country in Africa at the micro-scale of a parish. This foundational exploratory paper formed the first step of a broader study examining built environment factors explaining this pattern.