Primary Investigator: Kumar, Santosh mHealth Center for Discovery, Optimization & Translation of Temporally-Precise Interventions (mDOT) ? Overall Abstract: Providing care for patients with chronic diseases is one of the biggest drivers of the nation?s rising healthcare spending. Many of these diseases are inextricably linked to mutable health behaviors such as poor diet, lack of physical activity, and smoking. A key strategy for making self-care and preventive health behaviors more achievable has been the integration of passive monitoring into everyday life via mobile sensors and providing personalized information and guidance to patients. But, to have the maximum long-term efficacy, such mHealth interventions must be delivered at the most opportune moment and its content must be dynamically personalized to the individual, their current context, and changing preferences. Our proposed mHealth Center for Discovery, Optimization & Translation of Temporally-Precise Interventions (the mDOT Center) will provide the methods, tools, and infrastructure for researchers to discover, optimize and deploy temporally-precise mHealth interventions. Organized around three Technology Research & Development (TR&D) projects, mDOT represents a unique national resource that will develop multiple methodological and technological innovations, including easily deployable wearables, apps for wearables and smartphones, and a companion mHealth cloud system, all open-source. TR&D1 will develop, evaluate and disseminate methods to analyze population-scale multi-modal time series of mHealth biomarkers to identify the momentary risk factors and risk dynamics that drive adverse health outcomes, while accounting for the uncertainty and missingness inherent in these data sources. TR&D2 will develop new reinforcement learning methods to personalize the selection and delivery of mHealth interventions to individuals at their own optimal times and locations so as to maintain user engagement and provide precise and maximal health benefits. TR&D3 will develop, validate and disseminate algorithms, tools and software/hardware designs that will enable large-scale deployment of resource-efficient, real-time, low-latency and privacy-aware digital biomarkers. Together, these mDOT deliverables will transform the ability of researchers and innovators to exploit the exploding range of sensors and mobile technologies to develop and deliver dynamically personalized and temporally-precise mHealth interventions to individuals. The iterative ?push-pull? interaction with collaborative projects (CP) and direct dissemination to service projects (SP?s) will ensure that the technologies developed by our TR&Ds? solve real- world problems, are usable by other researchers, and will have the broadest impact. The mDOT Center?s training and dissemination (T&D) activities will seek to maximize the societal impact of our technologies by promoting broad distribution and uptake of mDOT technologies and resulting software beyond mDOT affiliates. Finally, a unifying mDOT administrative core and optimized operating procedures will facilitate interactions among TR&D researchers and their associated CPs and SPs; assess the productivity and impact of Center activities; and provide ongoing management, oversight, and planning. 1