# Clinical validation of a novel hand dexterity measurement device

## TL;DR

A new hand-worn sensor was developed and validated to objectively measure hand dexterity, showing promise for clinical trials and patient care.

## Contribution

A novel hand-worn sensor digitizing the Finger Tapping Test was developed and clinically validated for objective dexterity assessment.

## Key findings

- The device generated a dexterity score that was significantly lower in ALS patients compared to healthy controls.
- The device had a higher completion rate than traditional hand dexterity tests.
- The device's scoring system accounts for age and sex differences.

## Abstract

The lack of sensitive objective outcome measures for hand dexterity is a barrier for clinical assessment of neurological conditions and has negatively affected clinical trials. Here, we clinically validate a new method for measuring hand dexterity, a novel hand worn sensor that digitises the Finger Tapping Test. The device was assessed in a cohort of 180 healthy controls and 51 people with Amyotrophic Lateral Sclerosis (ALS) and compared against rating scales and traditional measures (Nine Hole Peg test and grip dynamometry). 14 features were extracted from the device and using a logistic regression algorithm, a 0-100 dexterity performance score was generated for each participant, which accounted for age/sex differences. The device returned objective ratings of a participant’s hand dexterity (dominant, non-dominant and overall score). The average overall dexterity performance score in all healthy participants was 88 ± 17 (mean ± standard deviation). The overall dexterity score was statistically significantly worse in participants with ALS (age/sex matched healthy subset: 80 ± 20, ALS: 45 ± 32, p-value < 0.0001). The device also had a higher completion rate, (94% dominant hand) compared to the traditional measures (82% dominant hand). This test and scoring system have been validated and the regression model was developed using a framework that is potentially applicable to any relevant condition. This device could act as an objective outcome measure in clinical trials and may be useful in improving patient care.

Clinical hand dexterity assessment methods have remained static for decades. Issues including subjectivity, floor effects and clinical accessibility have not been conclusively resolved. We have developed a novel hand worn sensor that digitises a common neurological test, the Finger Tapping Test. In this study we present the results of a large validation study (180 healthy controls and 51 people with Amyotrophic Lateral Sclerosis) which has provided a test and scoring system for hand dexterity measurement that returns an objective dexterity performance score. Unlike the current gold standard rating scales, it is not affected by hand dominance. Our device accounts for age/sex differences and has a higher completion rate than the other traditional tests. The device presented here has the potential to act as an objective outcome measure in clinical trials. We believe it has significant advantages over the current methods which were developed decades ago. Hope for improvements in treatments for neurodegenerative conditions relies on sensitive detection of meaningful change in function in clinical trials of new therapies. Drug companies and clinical trial providers will only adopt proven, sensitive digital devices and the device described provides an opportunity for such change.