From: The challenges faced in the design, conduct and analysis of surgical randomised controlled trials
Study characteristic | Exploratory trial | Explanatory trial | Pragmatic trial |
---|---|---|---|
Aim of evaluation | To explore the impact of the intervention | To assess whether the intervention is efficacious | To assess whether the intervention is effective |
Patient population | Initially those presumed to be most likely to benefit, though later modification is allowed | Narrow inclusion criteria of patients expected to be most suited to treatment | Broad inclusion criteria reflecting variations in clinical practice between centres |
Surgical setting | Surgeon(s) with substantial generic surgical expertise | Surgeon(s) with expertise in the intervention under evaluation | Surgeons from multiple centres representing different levels of expertise |
Intervention definition | Freedom to develop and refine | Tight definition and strictly controlled | Broader definition incorporating variations which reflect clinical practice |
Outcomes of main focus | Surgical process and short-term clinical outcomes | Short-term (sometimes surrogate) clinical outcomes | Longer-term clinical and patient-reported outcomes (such as quality of life measures) |