Smartphone-based patient self-assessment of neuropathy grade: a validation study of the neuropathy tracker alignment...

Repeated evaluation for grading of symptoms and signs in distal symmetrical peripheral neuropathy (DSPN) is a core aspect of patient care and inflicts a burden on both the patient and the healthcare system. We designed the smartphone-based Neuropathy Tracker to enable patients to document symptoms and perform a guided self-examination of signs of neuropathy by themselves. We investigate the alignment and classification strength of this grading with grading performed by professionals.

We included 21 patients with DSPN and 18 controls. In a test-retest paradigm, the patients used the Neuropathy Tracker, and they had examinations by clinical professionals to grade their neuropathy using the Utah Early Neuropathy Scale (UENS) and the Total Neuropathy Score - Clinical Version (TNSc). Further, they had quantitative examinations of Temperature Thresholds and Nerve Conduction Studies for amplitudes of Sural Sensory Nerve Action Potentials.

In a Bland-Altman analysis of differences between repeated tests, we found similar 95% confidence limits between Neuropathy Tracker and UENS, while TNSc had fewer wide limits. The comparison between the Neuropathy Tracker and UENS showed no bias in test score differences. Classification with receiver operating curve analysis showed Neuropathy Tracker to be slightly inferior to UENS and TNSc to classify neuropathy, but still with excellent ability, with area under curve values of 0.903±0.053.

Patient-administered neuropathy grading using the Neuropathy Tracker could add to the clinical evaluation in DSPN without an in-person visit to the outpatient clinic.