Validation of a constrained-time movement task for use in rehabilitation outcome measures.

Current motor assessment tools can provide numerical indicators of performance but do not provide actionable information to target further improvement in rehabilitation interventions. Psychophysics-based outcome measures show promise to provide more useful information in the laboratory environment but have been limited in clinical implementation. Here we present a constrained-time task to assess paced and non-rhythmic movements. The task's output metrics include trial-by-trial adaptation rate and the just noticeable difference of a perturbation. We show that the task's metrics are reliable (i.e. high test-retest reliability) and are responsive to changes in feedback type and experience. We also discuss the task's versatility to be used for other types of movements including grasping. The consistent, sensitive and flexible time-constrained movement task we present provides a foundation from which to develop advanced outcome measures for prosthesis users and for other rehabilitation contexts.