Evaluative design
Judge merit, effects and implementation
Evaluative design assesses an intervention, service or policy against explicit questions and criteria. Process evaluation examines implementation and mechanisms; outcome or impact evaluation examines changes, with causal claims needing a defensible counterfactual. Evaluation can also address acceptability, costs and equity. Formative work informs improvement, while summative work supports judgements about an established programme.
Use when stakeholders need to decide whether to adopt, improve, continue or scale an intervention, and the programme theory, decision criteria and access to relevant evidence can be specified.
Strengths
- Connects findings to concrete decisions
- Can explain implementation alongside outcomes and equity
Limitations
- Sponsor interests can influence criteria and reporting
- Before-after improvement may reflect external changes
Know the boundary
Monitoring activity counts is not necessarily evaluation, and satisfaction does not establish effectiveness.