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Med."],"abstract":"<jats:title>Abstract<\/jats:title><jats:p>Smartphones and wearables are widely recognised as the foundation for novel Digital Health Technologies (DHTs) for the clinical assessment of Parkinson\u2019s disease. Yet, only limited progress has been made towards their regulatory acceptability as effective drug development tools. A key barrier in achieving this goal relates to the influence of a wide range of sources of variability (SoVs) introduced by measurement processes incorporating DHTs, on their ability to detect relevant changes to PD. This paper introduces a conceptual framework to assist clinical research teams investigating a specific Concept of Interest within a particular Context of Use, to identify, characterise, and when possible, mitigate the influence of SoVs. 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(at time of writing at C-Path): No competing interests to declare. G.R.: is a technical advisor to the Critical Path for Parkinson\u2019s Consortium (CPP). T.R.H.: at time of writing Project Lead of Digital and Quantitative Medicine at Biogen. D.H.: is President of Panoramic Digital Health. A.V.D.: is Director of Digital Strategy at Takeda. J.C.: is Director of Digital Health Strategy at AbbVie and Industry Co-Director of CPP. L.E.: has received funding from the Michael J Fox Foundation for Parkinson\u2019s Research, UCB Biopharma, Stichting ParkinsonFonds, the Dutch Ministry of Economic Affairs, and ZonMw. A.D.: is Digital Biomarker Sensor Lead & Senior Scientist at Roche. K.F.: at time of writing Senior Director of Digital and Quantitative Medicine at Biogen. K.P.K.: Scientist at Biogen. N.M.: at time of writing Senior Principal Scientist of Quantitative Pharmacology and Pharmacometrics at Merck. R.D.: has stock ownership in Grand Rounds, an online second opinion service, has received consultancy fees from 23andMe, Abbott, Abbvie, Amwell, Biogen, Clintrex, CuraSen, DeciBio, Denali Therapeutics, GlaxoSmithKline, Grand Rounds, Huntington Study Group, Informa Pharma Consulting, medical-legal services, Mednick Associates, Medopad, Olson Research Group, Origent Data Sciences, Inc., Pear Therapeutics, Prilenia, Roche, Sanofi, Shire, Spark Therapeutics, Sunovion Pharmaceuticals, Voyager Therapeutics, ZS Consulting, honoraria from Alzheimer\u2019s Drug Discovery Foundation, American Academy of Neurology, American Neurological Association, California Pacific Medical Center, Excellus BlueCross BlueShield, Food and Drug Administration, MCM Education, The Michael J Fox Foundation, Stanford University, UC Irvine, University of Michigan, and research funding from Abbvie, Acadia Pharmaceuticals, AMC Health, BioSensics, Burroughs Wellcome Fund, Greater Rochester Health Foundation, Huntington Study Group, Michael J. Fox Foundation, National Institutes of Health, Nuredis, Inc., Patient-Centered Outcomes Research Institute, Pfizer, Photopharmics, Roche, Safra Foundation. J.A.: has received honoraria from Huntington Study Group, research support from National Institutes of Health, The Michael J Fox Foundation, Biogen, Safra Foundation, Empire Clinical Research Investigator Program, and consultancy fees from VisualDx and Spark Therapeutics.","order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"93"}}