Smartphone-based evaluation of parkinsonian hand tremor: Quantitative measurements vs clinical assessment scores

Abstract

With an ever-growing number of technologically advanced methods for the diagnosis and quantification of movement disorders, comes the need to assess their accuracy and see how they match up with widely used standard clinical assessment tools. This work compares quantitative measurements of hand tremor in twenty-three Parkinson's disease patients, with their clinical scores in the hand tremor components of the Unified Parkinson's Disease Rating Scale (UPDRS), which is considered the "gold standard" in the clinical assessment of the disease. Our measurements were obtained using a smartphone-based platform, which processes the phone's accelerometer and gyroscope signals to detect and measure hand tremor. The signal metrics used were mainly based on the magnitude of the acceleration and the rotation rate vectors of the device. Our results suggest relatively strong correlation (r>0.7 and p<;0.01) between the patients' UPDRS hand tremor scores and the signal metrics applied to the measured signals.

Assessment of Head Tremor with Accelerometers Versus Gyroscopic Transducers

“…Accelerometers and gyroscopes are used commonly in the assessment of hand tremor, but there are only a few published studies in which accelerometry was used to assess head tremor and no reports in which gyroscopes were used. In general, body motion has six degrees of freedom: three‐dimensional (3D) translation and 3D rotation.…”

An Ambulatory Tremor Score for Parkinson’s Disease

“…There are numerous examples of the use of accelerometry to analyse the tremor of PD, especially with the advent of easily accessible, high quality accelerometers in smart phones [10][11][12][13][14] and well established tremor detection algorithms [15,16]. We have described an accelerometer-based system for automated assessment of dyskinesia and bradykinesia [9].…”

Development of an Assessment Method of Forearm Pronation/Supination Motor Function based on Mobile Phone Accelerometer Data for an Early Diagnosis of Parkinson’s Disease

“…Measurements of PDrelated hand tremors were obtained with acceleration waveforms sampled at multiple sampling rates during 20 trials of simulated tremors compared to a static control. Kostikis et al compared quantitative measurements, which used four metrics obtained with a smartphone-based platform, of hand tremor in 23 PD patients using UPDRS grade [18]. An Android application was proposed to quantify Parkinson's disease tremors during the execution of routine movements through the use of a smartphone´s accelerometer [19].…”