Table 1 Example research questions and methods for evaluating each process
Domain | Example research questions | Research methods that could be applied | Probable best stage of study to collect data |
|---|---|---|---|
Recruitment of clusters | How are clusters sampled and recruited? | Documentation of recruitment process by research team. | Pre-intervention |
Who agrees to participate? | Quantitative comparison of recruited and nonrecruited clusters. | ||
Why do clusters agree to participate (or not) | Qualitative analysis of interviews with cluster gatekeepers or members. | ||
Delivery to clusters | What intervention is actually delivered for each cluster? Is it the one intended by the researchers? | Qualitative analysis of observational, interview and documentary data relating to the cluster-level intervention. | Pre-intervention and early intervention |
Response of clusters | How is the intervention adopted by clusters? | Quantitative data measuring cluster members’ perceptions of the intervention and uptake of trial components. Qualitative analysis of observational, interview and documentary data about how clusters adopt the intervention. | Pre-intervention and early intervention |
Recruitment and reach in individuals | Who actually receives the intervention in each setting? Are they representative? | Measurement of receipt in target population. Quantitative comparison of those receiving vs. not receiving the intervention. | During intervention |
Why do clusters achieve the pattern of reach they do? Do they introduce selection bias? | Qualitative analysis of observational, interview and documentary data about how clusters achieve reach. | ||
Delivery to individuals | What intervention is actually delivered for each cluster? | Qualitative analysis of observational, interview and documentary data about what intervention is delivered and why. | During intervention |
Is the delivered intervention the one intended by the researchers? | Measurement of intervention fidelity across its components. | ||
Response of individuals | How does the target population respond? | Qualitative analysis of observational and interview data about target population’s experience of and response to the intervention. | During intervention and post-intervention |
Maintenance | How and why are these processes sustained over time (or not)? | Any of the above, but probably focused on processes identified as critical, or as likely to be difficult to sustain. | During intervention and post-intervention |
Unintended consequences | Are there unintended changes in processes and outcomes, both related to the trial intervention and unrelated care? | Qualitative analysis of observational and interview data for identification. Quantitative data collection for potential unintended consequences during the trial, or use of routine datasets. | Intervention and post-intervention |
Theory | What theory has been used to develop the intervention? | Quantitative process data analysis can assess whether predicted relationships and sequences of change happened during implementation. | Post-intervention |
Context | What is the wider context in which the trial is being conducted? | Qualitative data collection from policy documents or interviews. | Pre-intervention and early intervention |