Remote Assessments of Hand Function in Neurological Disorders: Systematic Review.

The 74 studies measured too many different things in too many different ways, and used different comparison tests and statistical approaches, so the tools cannot be compared directly with one another. Most participants had mild to moderate disease, so these tools may behave differently in people with more severe hand impairment. Only 20% of studies reported reliability, and few repeated the assessment, so it is unclear how stable the measurements are or whether people improve simply through familiarity with the task. Confounders such as medication, age and disease duration were rarely accounted for in the validity statistics, so the results should be generalised cautiously. Every tool needed the patient to actively perform a task; passive monitoring was not tested. Only 2 of 74 studies reported any safety information. The search was limited to English-language publications, so relevant studies in other languages may have been missed.

The review itself reports no funding source. One author is supported by the National Multiple Sclerosis Society. Another receives research support to his university from Biogen and Roche Genentech, and personal consulting fees from Alexion, Biogen, EMD Serono, Genzyme Sanofi, Novartis and Roche Genentech, all companies that make neurological or multiple sclerosis drugs.

Do not read this as remote hand assessment being ready to replace in-clinic testing. The authors' own principal finding is that no single tool or combination validly and reliably captures hand function across these conditions, most of the reported associations with in-clinic measures were not statistically significant, and most of the evidence comes from people with mild to moderate Parkinson's disease.