Findings
Verification involves testing the accelerometer’s technical specifications (e.g., accuracy and precision) through peer-reviewed studies.
Validation of the algorithm relies on “ground truth” data, gathered through infrared video recordings and manual scoring of movements.
Cross-validation was used to assess the algorithm’s performance, with additional validation in independent samples planned.
The separation of verification and validation allows greater flexibility, enabling the algorithm’s use with multiple accelerometer devices that meet minimum standards.

Recommendations
Conduct separate verification and validation processes to ensure the reliability of both the device and the algorithm.
Use peer-reviewed publications to document the performance of DHTs and their limitations.
Ensure validation includes testing with representative populations to confirm the algorithm’s utility across diverse contexts.
Promote industry-wide standards to facilitate scalability and regulatory acceptance of DHTs in clinical trials.

Regulatory Considerations
Ensure DHTs undergo rigorous verification to meet accuracy and precision standards documented in peer-reviewed studies.
Validate algorithms using empirical “ground truth” data to demonstrate their ability to measure clinically meaningful outcomes.
Align the design and validation of DHTs with regulatory expectations for reliable and transferable performance across devices.