Exploring implementation outcomes in the clinical trial context: a qualitative study of physician trial stakeholders

Cancer clinical trials can be considered evidence-based interventions with substantial benefits, but suffer from poor implementation leading to low enrollment and frequent failure. Applying implementation science approaches such as outcomes frameworks to the trial context could aid in contextualizing and evaluating trial improvement strategies. However, the acceptability and appropriateness of these adapted outcomes to trial stakeholders are unclear. For these reasons, we interviewed cancer clinical trial physician stakeholders to explore how they perceive and address clinical trial implementation outcomes.

We purposively selected 15 cancer clinical trial physician stakeholders from our institution representing different specialties, trial roles, and trial sponsor types. We performed semi-structured interviews to explore a previous adaptation of Proctor's Implementation Outcomes Framework to the clinical trial context. Emergent themes from each outcome were developed.

The implementation outcomes were well understood and applicable (i.e., appropriate and acceptable) to clinical trial stakeholders. We describe cancer clinical trial physician stakeholder understanding of these outcomes and current application of these concepts. Trial feasibility and implementation cost were felt to be most critical to trial design and implementation. Trial penetration was most difficult to measure, primarily due to eligible patient identification. In general, we found that formal methods for trial improvement and trial implementation evaluation were poorly developed. Cancer clinical trial physician stakeholders referred to some design and implementation techniques used to improve trials, but these were infrequently formally evaluated or theory-based.

Implementation outcomes adapted to the trial context were acceptable and appropriate to cancer clinical trial physician stakeholders. Use of these outcomes could facilitate the evaluation and design of clinical trial improvement interventions. Additionally, these outcomes highlight potential areas for the development of new tools, for example informatics solutions, to improve the evaluation and implementation of clinical trials.