Relating sensor-based tremor metrics to a conventional clinical scale

Clinical scales based on visual observation are routinely used to assess pathological tremors, informing diagnoses and treatment selection. Because these scales incorporate elements that are subjective and limited in accuracy, sensor-based measurements of tremor are increasingly being considered as a means of improving on current practice. The translational potential of such measurement systems can be limited by their complexity and insufficient characterisation of how the new measures relate to the established scales and the prior literature that is based on those scales. In this study, we considered two simple sensor-based measures of tremor amplitude and compared them against an established clinical scale, the Fahn-Tolosa-Marin Tremor Rating Scale, among a cohort of 21 people with multiple sclerosis. Both metrics were found to be strongly correlated with the clinical scores (Pearson´s r = 0.83 in both cases). Sources of discrepancy are discussed, suggesting avenues for further refinement of tremor assessment methods.