Reliability and validity of the Roche PD Mobile Application for remote monitoring of early Parkinson's disease

Abstract

Digital health technologies enable remote and therefore frequent measurement of motor signs, potentially providing reliable and valid estimates of motor sign severity and progression in Parkinson's disease (PD). The Roche PD Mobile Application v2 was developed to measure bradykinesia, bradyphrenia and speech, tremor, gait and balance. It comprises 10 smartphone active tests (with ½ tests administered daily), as well as daily passive monitoring via a smartphone and smartwatch. It was studied in 316 early-stage PD participants who performed daily active tests at home then carried a smartphone and wore a smartwatch throughout the day for passive monitoring (study NCT03100149). Here, we report baseline data. Adherence was excellent (96.29%). All pre-specified sensor features exhibited good-to-excellent test-retest reliability (median intraclass correlation coefficient = 0.9), and correlated with corresponding Movement Disorder Society-Unified Parkinson's Disease Rating Scale items (rho: 0.12-0.71). These findings demonstrate the preliminary reliability and validity of remote at-home quantification of motor sign severity with the Roche PD Mobile Application v2 in individuals with early PD.

Figure 1

Roche PD Mobile Application v2 active tests and passive monitoring and schedule of assessments. eSDMT, electronic Symbol Digit Modalities Test; PD, Parkinson’s disease.

Figure 2

Absolute Spearman’s correlations between baseline MDS-UPDRS Total and Subscores and Roche PD Mobile Application v2 active test and passive monitoring sensor features. eSDMT electronic Symbol Digit Modalities Test, MDS-UPDRS Movement Disorder Society—Unified Parkinson's Disease Rating Scale, PD Parkinson’s disease, PIGD Postural Instability/Gait Disorders.

Figure 3

Association of sensor features from upper limb bradykinesia tests and upper limb tremor tests with corresponding clinical MDS-UPDRS measures at baseline (ns = P > 0.05; * = P ≤ 0.05; ** = P ≤ 0.01; *** = P ≤ 0.001; **** = P ≤ 0.0001). L less affected side, M more affected side, MDS-UPDRS Movement Disorder Society—Unified Parkinson's Disease Rating Scale, UE Upper Extremity.

Figure 4

Association of sensor features from Phonation/Speech and eSDMT tests with corresponding clinical MDS-UPDRS measures at baseline (ns = P > 0.05; * = P ≤ 0.05; ** = P ≤ 0.01; *** = P ≤ 0.001; **** = P ≤ 0.0001). eSDMT electronic Symbol Digit Modalities test, MDS-UPDRS Movement Disorder Society—Unified Parkinson's Disease Rating Scale, MFCC2 Mel Frequency Cepstral Coefficient 2.

Figure 5

Association of sensor features from U-turn, Balance tests and Passive monitoring of gait with corresponding clinical MDS-UPDRS measures at baseline (ns = P > 0.05; * = P ≤ 0.05; ** = P ≤ 0.01; *** = P ≤ 0.001; **** = P ≤ 0.0001). MDS-UPDRS Movement Disorder Society—Unified Parkinson's Disease Rating Scale.

Figure 6

Correlations between active test sensor features from the more and less affected sides (M and L, respectively) with MDS-UPDRS Part III item scores evaluating M and L. L less affected side, M more affected side, MDS-UPDRS Movement Disorder Society—Unified Parkinson's Disease Rating Scale.