To enhance the robustness of public policy, it is important to promote theory-based evaluation, including the use of logic models, as a form of “quasi-EBPM” (Evidence-Based Policymaking).
Theory-based evaluation involves articulating the hypothesized causal chain of a policy intervention, from inputs to activities, outputs, outcomes, and ultimately, impacts. It also seeks to explain why and through what mechanisms the links between these stages are expected to occur.
The credibility of a logic model can be strengthened by demonstrating the validity of its causal links through existing empirical evidence and established theories from the social sciences.
A logic model remains hypothetical until its validity has been empirically tested and verified. Policymakers should recognize that even a highly plausible logic model may be incorrect, and therefore it is important to examine whether its assumptions and causal pathways hold in practice.
In Japan, ex ante evaluations such as theory-based evaluation have often been conducted primarily to justify policies after their substantive content has already been decided. This practice diverges from the original purpose of theory-based evaluation. Ideally, theory-based evaluation should be integrated into the policy decision-making process itself.
