In a Digital Version of the 9-Hole Peg Test, Intra-Task Speed, Accounting for Variance in Distance Traveled, May be a Better Measure of MS-Related Upper-Limb Disability Than Completion Time. (P3-3.006) (2023)

<h3>Objective:</h3> To determine if speed is a better measure of MS-related decline in upper limb function than the current standard of completion time utilizing a digital version of the 9-hole peg test (MDT). <h3>Background:</h3> MDT completion time reflects both the speed and distance travelled during the task. How each contributes to the variance and whether each is related to MS disease worsening can be measured. <h3>Design/Methods:</h3> Assessments were acquired using the Multiple Sclerosis Performance Test (MSPT) within the MS PATHS network. ‘Distance’ was the summed direct distance between every consecutive peg movement. ‘Speed’ was the summed direct distance per second of completion time. Intra-patient longitudinal change associations between MDT measures and Patient-Determined Disease Steps (PDDS), Processing Speed Test (PST), and Neuro-QoL scores were assessed by repeated measure correlations. Intra-patient minimum and maximum distance and dispersion (SD/mean) for speed and completion time were calculated in patients with &gt;2 MDT assessments. Cox-models were used to assess covariates predicting time to 20% confirmed worsening (T20%CW) in completion time after 2 years. <h3>Results:</h3> Speed and completion time showed similar significant longitudinal associations with PDDS, PST, and Neuro-QoL upper extremity scores; distance was not associated. Intra-patient distance varied substantially between assessments; 62% of patients had &gt;10cm; 27% had &gt;20cm differences. Speed had lower dispersion than completion time. T20%CW in completion time models had better Akaike information criterion and Bayesian information criterion values, indicating better fit, when speed was used as the predictive covariate versus completion time. Adding speed to models with completion time significantly improved model performance; adding completion time to those with speed yielded no improvement. <h3>Conclusions:</h3> MDT completion time longitudinal changes have variance contributed by fluctuating distances travelled between assessments that are unrelated to MS disease. Accounting for this variance by measuring speed lowers dispersion and improves predictive model performance for time to meaningful worsening. <b>Disclosure:</b> Xiaotong Jiang has nothing to disclose. Dr. McGinley has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Octave. Dr. McGinley has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Genentech. Dr. McGinley has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for EMD Serono. The institution of Dr. McGinley has received research support from Novartis. The institution of Dr. McGinley has received research support from Biogen. The institution of Dr. McGinley has received research support from Genentech. The institution of Dr. McGinley has received research support from NIH. Joshua Johnston has nothing to disclose. The institution of Dr. Alberts has received research support from NIH. Dr. Alberts has received intellectual property interests from a discovery or technology relating to health care. Dr. Alberts has received personal compensation in the range of $500-$4,999 for serving as a Member, Health and Wellness Council with Peloton Interactive. Dr. Bermel has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Biogen. Dr. Bermel has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Sanofi/Genzyme. Dr. Bermel has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Genentech/Roche. Dr. Bermel has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Viela Bio. Dr. Bermel has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Novartis. Dr. Bermel has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Merck Serono. Dr. Bermel has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Astra Zeneca. Dr. Bermel has received personal compensation in the range of $500-$4,999 for serving as a Consultant for LabCorp. Dr. Bermel has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for TG Therapeutics. The institution of Dr. Bermel has received research support from Biogen. The institution of Dr. Bermel has received research support from Roche. The institution of Dr. Bermel has received research support from Novartis. Dr. Bermel has received intellectual property interests from a discovery or technology relating to health care. Dr. Ontaneda has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Novartis. Dr. Ontaneda has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Genentech/Roche. Dr. Ontaneda has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Biogen Idec. Dr. Ontaneda has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Genentech/Roche. The institution of Dr. Ontaneda has received research support from NIH. The institution of Dr. Ontaneda has received research support from PCORI. The institution of Dr. Ontaneda has received research support from NMSS. The institution of Dr. Ontaneda has received research support from Genetech. Nicholas Levitt has received personal compensation for serving as an employee of Biogen Inc.. Dr. Van Beek has nothing to disclose. Nolan Campbell has received personal compensation for serving as an employee of Biogen. Nolan Campbell has stock in Biogen.