Using Digital Outcomes to Measure Meaningful Aspects of Health in Clinical Trials for Parkinson's Disease: A Scoping Review.

Background: The importance of considering the meaningfulness of digital measures is increasing with the expanding use of sensor-based monitoring in clinical trials. Regulatory guidelines emphasize measuring meaningful aspects of health specific to a patient population. Summary: Translating meaningful aspects of health into objective measures is not a trivial task. We review how researchers justify the use of digital endpoints in Parkinson's disease trials, with emphasis on meaningfulness to patients. A systematic search (ClinicalTrials.gov; ClinicalTrialsRegister.eu) yielded 45 trials using digital measures as primary or secondary endpoints. We performed a qualitative analysis of trial protocols to identify justifications for using digital endpoints. We found that justifications for meaningfulness were often presented for general health domains and rarely for specific digital endpoints. Moreover, explanation for meaningfulness to patients was often not made explicit, indicating a discrepancy between guidelines and research practice. Key Messages: Meaningfulness of specific digital measures to patients is often not explicitly justified and there is a disconnect between guidelines and research practice. Because of the complexity of linking meaningfulness to digital measures, there is a need for sharing examples and lessons learned, and for further developed and differentiated guidelines. Moreover, to foster true meaningfulness of digital measures to patients, there is a need for prioritizing measuring meaningful aspects of health as a central requirement for the development and selection of these measures. The lessons learned from the Parkinson's disease context may inspire and inform the adoption of digital endpoints in other disease areas.