This study examines process-control systems in South Africa, focusing on their application across various industries to improve efficiency and effectiveness. A randomized field trial was conducted across ten industries in South Africa, with a sample size of 50 sites per industry sector. Data collection involved pre- and post-trial measurements to evaluate system performance and cost metrics using linear regression models for cost-effectiveness analysis. The findings indicate that the implementation of advanced control systems led to an average reduction in operational costs by 12% across all sectors, with a standard error of ±3. 5%, suggesting robust reliability. The study concludes that randomized field trials are effective for evaluating process-control system cost-effectiveness and can inform policy decisions regarding investment in such technologies. Based on the findings, it is recommended that South African industries adopt a standardised approach to implementing control systems with periodic performance reviews to ensure continued efficiency gains. The maintenance outcome was modelled as Y₈ₓ=₀+₁X₈ₓ+uᵢ+₈ₓ, with robustness checked using heteroskedasticity-consistent errors.
Sathya Motsiwa (Sat,) studied this question.