title: Effects of an internet-based cognitive behavioural therapy intervention on preventing major depressive episodes among workers: a protocol for a randomised controlled trial.
abstract: BACKGROUND
  The aim of this study is to examine the effects of an internet-based cognitive behavioural therapy (iCBT) program on decreasing the risk of major depressive episodes (MDEs) among workers employed in a private corporate group in Japan, using a randomised controlled trial design.
  
  
  METHODS
  All of the workers in a corporate group (n=20,000) will be recruited through an invitation email. Participants who fulfil the inclusion criteria will be randomly allocated to intervention or control groups (planned N=4050 for each group). They will be allowed to complete the six lessons of the iCBT program within 10 weeks after the baseline survey. Those in the control group will receive the same iCBT after 12 months. The program includes several CBT skills: self-monitoring, cognitive restructuring, assertiveness, problem-solving and relaxation. The primary outcome measure is no new onset of MDE (using Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR)/DSM-5 criteria) during the 12-month follow-up. Assessment will use the web version of the WHO Composite International Diagnostic Interview V.3.0 depression section.
  
  
  BACKGROUND
  The Research Ethics Review Board of Graduate School of Medicine, the University of Tokyo (No. 3083-(2)), approved the study procedures.
  
  
  BACKGROUND
  The study protocol is registered at the UMIN Clinical Trials Registry (UMIN-CTR; ID=UMIN000014146).
authors.affiliation: Department of Mental Health, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Kotaro
authors.initials: K
authors.lastname: Imamura
authors.affiliation: Department of Mental Health, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Norito
authors.initials: N
authors.lastname: Kawakami
authors.affiliation: Departments of Health Promotion and Human Behavior and of Clinical Epidemiology, Graduate School of Medicine/School of Public Health, Kyoto University, Kyoto, Japan.
authors.forename: Toshi A
authors.initials: TA
authors.lastname: Furukawa
authors.affiliation: Department of Biostatistics, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Matsuyama
authors.affiliation: Department of Mental Health, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Akihito
authors.initials: A
authors.lastname: Shimazu
authors.affiliation: Department of Neuropsychiatry, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Kiyoto
authors.initials: K
authors.lastname: Kasai
mesh_terms: D000328:Adult; D002985:Clinical Protocols; D015928:Cognitive Behavioral Therapy / Q000379:methods*; D003865:Major Depressive Disorder / Q000517:prevention & control*; D005260:Female; D006801:Humans; D020407:Internet; D007564:Japan; D008297:Male; D008875:Middle Aged; D009784:Occupational Diseases / Q000517:prevention & control*; D011322:Primary Prevention; D013813:Therapy, Computer-Assisted; D055815:Young Adult
keywords: OCCUPATIONAL & INDUSTRIAL MEDICINE; PREVENTIVE MEDICINE