Accepted for/Published in: JMIR Formative Research
Date Submitted: Feb 24, 2023
Date Accepted: Aug 15, 2023
Assessment of Upper Extremity Function in Multiple Sclerosis: Feasibility of a Digital Pinching Test
ABSTRACT
Background:
The development of touchscreen-based assessments of upper extremity function could benefit people with multiple sclerosis (PwMS) by allowing convenient, quantitative assessment of their condition. The Pinching Test forms a part of the Floodlight smartphone application for PwMS and was designed to capture upper extremity function.
Objective:
To evaluate the Pinching Test as a tool for remotely assessing upper extremity function in PwMS.
Methods:
Using data from the 24-week, prospective feasibility study investigating the Floodlight Proof-of-Concept application for remotely assessing multiple sclerosis (MS) (NCT02952911), we examined 13 pinching, 11 inertial measurement unit (IMU)-based, and 13 fatigability features of the Pinching Test. We assessed: test–retest reliability using intraclass correlation coefficients [second model, first type] (ICC[2,1]), age- and sex-adjusted cross-sectional Spearman’s rank correlation, and known-groups validity (data aggregation: median [all features], standard deviation [SD; fatigability features]).
Results:
We evaluated data from 67 PwMS (mean Expanded Disability Status Scale [EDSS]: 2.4 [SD 1.4]) and 18 healthy controls. In this cohort of early MS, pinching features were reliable (ICC[2,1]=0.54-0.81); correlated with standard clinical assessments, including Nine-Hole Peg Test (9HPT) (│r│=0.26-0.54; 10/13 features), EDSS (│r│=0.25-0.36; 7/13 features), and Multiple Sclerosis Impact Scale (MSIS-29) arm items (│r│=0.31-0.52; 7/13 features); and differentiated PwMS-Normal from PwMS-Abnormal (Area Under the Curve: 0.68-0.78; 8/13 features). IMU-based features showed similar test–retest reliability (ICC[2,1]=0.47-0.84), but showed little correlations with standard clinical assessments. Contrastingly, fatigability features (SD aggregation) correlated with 9HPT (│r│=0.26-0.61; 10/13 features), EDSS (│r│=0.26-0.41; 8/13 features), and MSIS-29 arm items (│r│=0.32-0.46; 7/13 features).
Conclusions:
The Pinching Test provides a remote, objective, and granular assessment of upper extremity function in PwMS that can potentially complement standard clinical evaluation. Future studies will validate it in more advanced MS. Clinical Trial: ClinicalTrials.gov NCT02952911
Citation
Per the author's request the PDF is not available.
Copyright
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