Estimating the financial costs associated with a phase III, multi-site exercise intervention trial: Investigating Gains in Neurocognition in an Intervention Trial of Exercise (IGNITE).

Introduction: Supervised exercise interventions are expensive and time intensive. However, there are financial costs to consider in addition to the intervention itself, namely: advertising and recruitment, outcome assessments, and other trial-related costs.

Objectives: In this analysis, we examine the financial costs associated with the administration of Investigating Gains in Neurocognition in an Intervention Trial of Exercise (IGNITE) to quantify the costs associated with large exercise intervention trials and to provide future investigators with financial estimates if they wish to pursue studies of a similar design.

Methods: Cost per randomized participant were calculated in four areas: (1) advertising and recruitment, (2) outcome assessments, (3) delivery of the intervention, and (4) other trial-related expenses. Overall trial costs associated with data analysis, faculty salaries, and indirect costs were estimated as well.

Results: The total cost per randomized participant was estimated to be $16,494. Outcome assessments accounted for the highest proportion of per-participant (75%) and total trial (38%) costs. Neuroimaging assessments (MRI & PET) cost $8247 per randomized participant, accounting for two-thirds (67%) of outcome assessment costs and half (50%) of per-participant costs.

Conclusion: Large clinical trials of exercise are expensive (~$21 million), particularly when administering several visits to assess study aims. Outcome assessments, specifically those involving neuroimaging, accounted for a significant proportion of total costs in this analysis. Future investigators must budget accordingly if they wish to conduct a comprehensive, multi-site exercise intervention trial that examines numerous physiological and psychological outcomes.