Table 1 Framework for applying a realist orientation to reviewing evidence in population health intervention research

PLAN

Theorize about change dynamics and draw causal inferences.

Assess all interventions and factors in place that merit consideration as contributors to preventing incidence.

Paying particular attention to contextual factors as they relate to expected health outcomes for different populations, use empirical evidence from the literature as well as practice-based wisdom to inform planning processes.

IMPLEMENT

Be sensitive to stakeholder and end-user needs, which may differ significantly from researchers' goals.

While interventions must be replicable, they may require revisions to be effective in different contexts.

Practice the 'duty of care' for all participants in the intervention.

Gain insight into contextual factors and particularly mechanisms by which interventions may work differently in different contexts.

Consider which potential outcomes might be expected for different populations and sub-populations, and strategize means of tailoring implementations to be effective for different populations.

EVALUATE

Evaluate the intervention for:

- Relevance;

- Coherence between theory of problem and theory of change;

- Responsiveness to local conditions;

- Achievements, particularly health outcomes;

- Results and impact, or the relationship between the intervention and the change.

Use both supporting and contradicting evidence to gain further insight into the effects of context upon efficacy and impact of interventions for different populations and sub-populations.