Municipal water systems in Nigeria face challenges related to yield improvement, necessitating robust methodological evaluations. A systematic literature review approach was employed, including databases such as PubMed and Web of Science, with inclusion criteria based on specific keywords and study design types. Quasi-experimental designs predominantly focused on randomized controlled trials (RCTs) and difference-in-differences (DiD), though there were variations in implementation methods and outcomes. The review identified a growing interest among researchers but noted inconsistencies in data collection and analysis techniques, highlighting the need for standardization. Standardised guidelines for quasi-experimental designs should be developed to enhance comparability and reliability of yield improvement studies in municipal water systems. The empirical specification follows Y=₀+^ X+, and inference is reported with uncertainty-aware statistical criteria.
Nnamdi et al. (Mon,) studied this question.