Effectiveness of a Web-Based Cognitive-Behavioral Tool to Improve Mental Well-Being in the General Population: Randomized Controlled Trial

John Powell   ¹ , MBBChir, MSc, PhD, FFPH ;   Thomas Hamborg   ² , PhD ;   Nigel Stallard   ² , PhD ;   Amanda Burls   ¹ , MBBS, MSc, FFPH ;   Jaime McSorley   ³ ;   Kylie Bennett   ⁴ , BSc, BA(Hons) ;   Kathleen M Griffiths   ⁴ , BSc(Hons), PhD ;   Helen Christensen   ⁵ , PhD

¹ Department of Primary Care Health Sciences, University of Oxford, Oxford, United Kingdom

² Division of Health Sciences, Warwick Medical School, University of Warwick, Coventry, United Kingdom

³ NHS Choices, Department of Health, London, United Kingdom

⁴ Centre for Mental Health Research, The Australian National University, Canberra, Australia

⁵ Black Dog Institute, University of New South Wales, Randwick, Australia