Direct Measurements of Smartphone Screen-Time: Relationships with Demographics and Sleep

• Matthew A. Christensen,

  Affiliation Division of Cardiology, Department of Medicine, University of California San Francisco, San Francisco, California, United States of America

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• Laura Bettencourt,

  Affiliation Department of Epidemiology and Biostatistics, University of California San Francisco, San Francisco, California, United States of America

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• Leanne Kaye,

  Affiliation Ginger.io Incorporated, San Francisco, California, United States of America

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• Sai T. Moturu,

  Affiliation Ginger.io Incorporated, San Francisco, California, United States of America

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• Kaylin T. Nguyen,

  Affiliation Division of Cardiology, Department of Medicine, University of California San Francisco, San Francisco, California, United States of America

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• Jeffrey E. Olgin,

  Affiliation Division of Cardiology, Department of Medicine, University of California San Francisco, San Francisco, California, United States of America

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• Mark J. Pletcher,

  Affiliation Department of Epidemiology and Biostatistics, University of California San Francisco, San Francisco, California, United States of America

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• Gregory M. Marcus

  * E-mail: marcusg@medicine.ucsf.edu

  Affiliation Division of Cardiology, Department of Medicine, University of California San Francisco, San Francisco, California, United States of America

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