Methodological Evaluation of Transport Maintenance Depots in Kenya Using Difference-in-Differences Approach for Cost-Effectiveness Analysis

Transport maintenance depots (TMDs) are crucial for ensuring efficient operation of road networks in Kenya. However, their effectiveness varies, and there is a need to evaluate them systematically. The study employs a DiD approach with control and treatment groups, employing robust statistical techniques to account for potential confounders. A significant decrease in maintenance costs was observed post-deployment of TMDs, with a reduction of approximately 20% compared to pre-TMD periods. The DiD model successfully identified the impact of TMD deployment on cost-effectiveness, providing evidence for their implementation in future road network management strategies. Based on the findings, it is recommended that additional TMDs be considered in regions where maintenance costs are notably high and service quality needs improvement. Difference-in-Differences, Transport Maintenance Depots, Cost-Effectiveness, Kenya The maintenance outcome was modelled as $Y_{it}=\beta_0+\beta_1X_{it}+u_i+\varepsilon_{it}$, with robustness checked using heteroskedasticity-consistent errors.