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February 3, 2024

Landmark Randomized Controlled Trial Demonstrates Efficacy of Daylight™ Digital Therapeutic in Improving Anxiety


71% of Daylight users in the study achieved and maintained remission of Generalized Anxiety Disorder (GAD) by week 10 follow-up, compared to 33% of controls.

Study Conducted in Collaboration with the University of Oxford, Sleep & Circadian Neuroscience Institute

Oxford, UK and San Francisco, CA – Wednesday 29 July, 2020 — The University of Oxford’s Sleep & Circadian Neuroscience Institute, and Big Health, the global leader in digital therapeutics dedicated to bringing millions back to good mental health — today announced publication of a randomized controlled trial (RCT) assessing the efficacy and safety of Big Health’s Daylight product in improving symptoms of Generalized Anxiety Disorder (GAD), in the journal Depression and Anxiety. The Daylight digital therapeutic is a fully automated smartphone-based program that leverages evidence-based cognitive and behavioral techniques to help people deal with worry and anxiety.

The study found that Daylight significantly reduced symptoms of anxiety in trial participants, as compared to the control group at six weeks after intervention. By week 10 follow-up, 71% of Daylight users in the study achieved remission of GAD, as compared to 33% of those in the control group. Improvements were maintained at week 26 (uncontrolled) follow-up. The sustained maintenance of results is especially noteworthy since the 6-month follow up period coincided with the COVID-19 pandemic – a time of heightened anxiety for people throughout the world.

“This trial confirms that Daylight is a safe, effective first-line digital therapeutic for worry and anxiety,” said Professor Jasper Smits, PhD, Department of Psychiatry at the University of Texas, Austin. “The measurable, consistent improvements in mental health status achieved by Daylight users in this trial are significant and meaningful, giving us confidence that as software, Daylight can offer relief to people suffering from worry, anxiety and related conditions.”

Worry and anxiety can significantly interfere with people’s day-to-day functioning and overall quality of life. Anxiety is the most common mental health issue in the United States, affecting more than 40 million Americans (18 percent of the population) every year; GAD in particular, a mental health disorder characterized by excessive worry and anxiety that is difficult to control and is accompanied by unwanted physical symptoms and interference in functioning, affects 56 percent of the population annually in the UK and US, respectively. In the last six months, numerous surveys have reported increased rates of anxiety and stress due to the global pandemic.

“Anxiety and other mental health challenges cause distress to millions throughout the world, yet many people lack access to effective solutions, due to issues of stigma, or the supply constraints of in-person mental health care which have been further exacerbated by the COVID-19 pandemic,” said Dr. Jenna Carl, vice president of clinical development and medical affairs at Big Health. “The results of this study confirm that Daylight can have a meaningful impact on the people who need it most. We are excited about the potential for Daylight to help many millions more people back to good mental health, especially those who have limited access to in-person care.”

In the trial, 256 participants were randomized to either use Daylight or be part of a control group which would receive the intervention at a later date. Participants were included based on meeting criteria for GAD with moderate to severe symptoms, assessed using well-established clinical measures (MINI and SCID for diagnosis; GAD-7 for severity). Assessments took place at baseline (week 0, immediately preceding randomization), mid-intervention (week 3 from randomization), post-intervention (week 6, primary endpoint), follow-up (week 10) and long-term follow-up (week 26 uncontrolled follow-up).

Qualitative feedback from the trial’s participants was also positive and consistent:

“I really like the inclusion of animation..the combination of the visuals with the soothing voice of the instructor..this app has given me a lot more tools that I can and have been able to use to help control my anxiety. For the first time in a while, I actually feel like I am gaining control.”

“..the app is always there with you while you’re doing the exercises – it doesn’t just send you away to go and worry for 20 minutes, it’s those small touches that I found helped so much compared to any other CBT online course I’ve done (and never kept on with!).”

“It has given me tools when I experience anxiety to help manage it. Being able to cope better has given me more control of my life day to day.”

“I felt more confident in my ability to handle my anxiety and worries. I felt like I could prioritize tasks to keep my anxiety at bay. I also felt like worry time and thought challenger helped me be more able to challenge my worries and anxiety.”

The study was supported by Big Health. The study authors included:

  • Jenna R. Carl, Michelle L. Davis, Olivia Shin (Big Health)
  • Colin A. Espie, Alasdair L. Henry, Christopher B. Miller, Richard Stott, Jenny Gu (Big Health and University of Oxford)
  • Kate E.A. Saunders, Guy M. Goodwin (University of Oxford)
  • Michelle W. Craske (University of California Los Angeles)
  • Michael W. Otto (Boston University)
  • Jasper A.J. Smits (University of Texas at Austin)
  • Richard Emsley (King’s College London)

In 2020, the number of global smartphone users is projected to total 3.5 billion, or approximately 45 percent of the world’s population. In developed countries like the U.S. and the U.K., that percentage goes up to approximately 80 percent. The implications of these findings are that, with a fully automated smartphone-based delivery model, Daylight has the potential to provide safe and effective mental health support to the broad population in need.  

In creating Daylight, Big Health collaborated with top anxiety experts from Boston University, University of California, Los Angeles, University of Oxford and University of Texas, Austin to develop a program that effectively teaches individuals how to respond to negative thoughts, use their body to reduce stress and tension and face their fears directly. Users can come back at any time to check in, learn new techniques and measure their progress. Developed by leading podcast producers, filmmakers, designers and animators, including veterans of Pixar and the U.S.-based National Public Radio’s Radiolab, the Daylight program combines animation with the intimacy of the human voice to provide a fully immersive visual and auditory experience that is personalized, lighthearted and upbeat.

Daylight is Big Health’s second digital therapeutic, following the success of its first product, Sleepio™, a digital sleep improvement program accessible to millions of people worldwide through employers and payers including Boston Medical Center, Comcast, the Hartford and the U.K.’s National Health Service (NHS). Daylight has recently received CE mark approval, in recognition of meeting the safety and performance requirements for medical devices in the European Union (EU).

The results of this study are consistent with those of an earlier feasibility and efficacy study (Miller et al., under review), and together these studies provide compelling evidence of Daylight’s ability to help individuals manage and overcome difficulties with worry and anxiety. In addition to the primary outcomes on anxiety, statistically significant, moderate-to-large improvements were found for measures of worry, depressive symptoms, sleep difficulty, wellbeing and participant-specific quality of life1. The effects of Daylight did not differ between demographic groups or those with more severe symptoms at baseline.

About Big Health

Big Health’s purpose is to help millions back to good mental health, with digital therapeutics – fully automated and highly personalized behavioral programs for mental health. Big Health’s products are Sleepio™ for helping individuals address poor sleep; and Daylight™ for helping individuals address worry and anxiety. Designed by leading clinical experts, Big Health’s solutions feature evidence-based cognitive and behavioral techniques and are backed by more than 50 peer-reviewed research studies including 13 randomized controlled trials. With offices in London and San Francisco, Big Health’s products are used by large multinational employers and major health plans to help improve sleep and mental health, covering millions of employee lives. During the COVID-19 pandemic, Big Health has made Sleepio and Daylight available at no cost to self-insured employers across the US and to all NHS and frontline staff in the UK.

About the University of Oxford

Oxford University has been placed number 1 in the Times Higher Education World University Rankings for the third year running, and at the heart of this success is our ground-breaking research and innovation. Oxford is world-famous for research excellence and home to some of the most talented people from across the globe. Our work helps the lives of millions, solving real-world problems through a huge network of partnerships and collaborations. The breadth and interdisciplinary nature of our research sparks imaginative and inventive insights and solutions. Through its research commercialisation arm, Oxford University Innovation, Oxford is the highest university patent filer in the UK and is ranked first in the UK for university spinouts, having created more than 170 new companies since 1988. Over a third of these companies have been created in the past three years.,

About The Sleep & Circadian Neuroscience Institute

The Sleep & Circadian Neuroscience Institute are a group of scientists and doctors working on circadian timing and disease. Their purpose is to change the way we address major challenges of the 21st century: how to treat disease, discover new medicines and handle the longer wakening day. They are driving fundamental discoveries into the ancient systems that govern time in our lives. To learn more, click here.

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During the COVID-19 public health emergency, Sleepio and Daylight are being made available as treatments for insomnia disorder and generalized anxiety disorder (GAD), respectively, without a prescription. Sleepio and Daylight have not been cleared by the U.S. Food and Drug Administration (FDA) for the treatment of insomnia disorder and GAD, respectively.

1. Qaseem, A., Kansagara, D., Forciea, M. A., Cooke, M., & Denberg, T. D. (2016). Management of chronic insomnia disorder in adults: a clinical practice guideline from the American College of Physicians. Annals of Internal Medicine, 165(2), 125-133.2. Riemann, D., Baglioni, C., Bassetti, C., Bjorvatn, B., Dolenc Groselj, L., Ellis, J. G., … & Spiegelhalder, K. (2017). European guideline for the diagnosis and treatment of insomnia. Journal of Sleep Research, 26(6), 675-700.3. Wilson, S., Anderson, K., Baldwin, D., Dijk, D. J., Espie, A., Espie, C., … & Sharpley, A. (2019). British Association for Psychopharmacology consensus statement on evidence-based treatment of insomnia, parasomnias and circadian rhythm disorders: an update. Journal of Psychopharmacology, 33(8), 923-947.4. King’s Technology Evaluation Centre. (2017, November 9). Overview: Health app: SLEEPIO for adults with poor Sleep: Advice. NICE. Espie, C. A., Kyle, S. D., Williams, C., Ong, J. C., Douglas, N. J., Hames, P., & Brown, J. S. (2012). A randomized, placebo-controlled trial of online cognitive behavioral therapy for chronic insomnia disorder delivered via an automated media-rich web application. Sleep, 35(6), 769-781.6. Carl, J. R., Miller, C. B., Henry, A. L., Davis, M. L., Stott, R., Smits, J. A., … & Espie, C. A. (2020). Efficacy of digital cognitive behavioral therapy for moderate‐to‐severe symptoms of generalized anxiety disorder: A randomized controlled trial. Depression and Anxiety, 37(12), 1168-1178.

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