The IDEAL Framework describes the stages through which interventional therapy innovation normally passes, the characteristics of each stage and the study design types which we have recommended for each.
The remainder of this page contains extracts from McCulloch et al, Lancet 2009; Sep 26; 374 (9695): 1105-12.
Peter McCulloch, Douglas G Altman, W Bruce Campbell, David R Flum, Paul Glasziou, John C Marshall, Jon Nicholl, for the Balliol Collaboration
Surgery and other invasive therapies are complex interventions, the assessment of which is challenged by factors that depend on operator, team, and setting, such as learning curves, quality variations, and perception of equipoise.
We propose recommendations for the assessment of surgery based on a five-stage description of the surgical development process.
We also encourage the widespread use of prospective databases and registries. Reports of new techniques should be registered as a professional duty, anonymously if necessary when outcomes are adverse.
Case series studies should be replaced by prospective development studies for early technical modifi cations and by prospective research databases for later pre-trial evaluation.
Protocols for these studies should be registered publicly.
Statistical process control techniques can be useful in both early and late assessment. Randomised trials should be used whenever possible to investigate efficacy, but adequate pre-trial data are essential to allow power calculations, clarify the definition and indications of the intervention, and develop quality measures.
Difficulties in doing randomised clinical trials should be addressed by measures to evaluate learning curves and alleviate equipoise problems. Alternative prospective designs, such as interrupted time series studies, should be used when randomised trials are not feasible.
Established procedures should be monitored with prospective databases to analyse outcome variations and to identify late and rare events.