title: Short-term effectiveness of web-based guided self-help for phobic outpatients: randomized controlled trial.
abstract: BACKGROUND
  Internet-based guided self-help has been successfully used in the general population, but it is unknown whether this method can be effectively used in outpatient clinics for patients waiting for face-to-face psychotherapy for phobias.
  
  
  OBJECTIVE
  The aim was to assess the clinical effectiveness of Phobias Under Control, an Internet-based intervention based on exposure therapy with weekly guidance.
  
  
  METHODS
  We conducted a randomized controlled trial, recruiting 212 outpatients scheduled to receive face-to-face psychotherapy for any type of phobia at an outpatient clinic. Participants suffering from at least 1 DSM-IV or ICD-10 classified phobia (social phobia, agoraphobia with or without panic disorder, and/or specific phobia as ascertained by a telephone interview at baseline) were randomly allocated to either a 5-week Internet-based guided self-help program based on exposure therapy with weekly student support followed by face-to-face psychotherapy (n=105) or a wait-list control group followed by face-to-face psychotherapy (n=107). Primary outcome was the Fear Questionnaire (FQ). Secondary outcomes were the Beck Anxiety Inventory (BAI) and Center of Epidemiological Studies-Depression scale (CES-D). Assessments took place by telephone at baseline (T0) and on the Internet at posttest (T1, self-assessment at 5 weeks after baseline). Missing data at T1 were imputed.
  
  
  RESULTS
  At posttest, analysis of covariance on the intention-to-treat sample showed significant but small effect sizes between intervention and control groups on the FQ (d=0.35, P=.02), CES-D (d=0.34, P=.03), and a nonsignificant effect size on the BAI (d=0.28. P=.05). Although initial acceptance was good, high nonresponse was observed, with 86 of 212 participants (40.5%) lost to follow-up at T1 and only 14 of 105 (13.3%) intervention participants finishing all 5 weeks.
  
  
  CONCLUSIONS
  Phobias Under Control is modestly effective in lowering phobic and depressive symptoms in a relatively short period and may be clinically beneficial when implemented in routine outpatient practice.
  
  
  BACKGROUND
  Netherlands Trial Register NTR2233; http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=2233 (Archived by WebCite at http://www.webcitation.org/6O2ioOQSs).
authors.affiliation: Department of Clinical Psychology and the EMGO institute for Health and Care Research, VU University Amsterdam, Amsterdam, Netherlands. r.n.kok@vu.nl.
authors.forename: Robin N
authors.identifier: http://orcid.org/0000-0001-9845-282X
authors.initials: RN
authors.lastname: Kok
authors.forename: Annemieke
authors.identifier: http://orcid.org/0000-0001-6875-2215
authors.initials: A
authors.lastname: van Straten
authors.forename: Aartjan T F
authors.identifier: http://orcid.org/0000-0003-2382-1410
authors.initials: AT
authors.lastname: Beekman
authors.forename: Pim
authors.identifier: http://orcid.org/0000-0001-5497-2743
authors.initials: P
authors.lastname: Cuijpers
mesh_terms: D000328:Adult; D000553:Ambulatory Care; D003863:Depression / Q000628:therapy*; D005260:Female; D015438:Health Behavior; D006801:Humans; D007171:Implosive Therapy / Q000379:methods* / Q000458:organization & administration; D020407:Internet; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D010698:Phobic Disorders / Q000628:therapy*; D016730:Program Development; D012647:Self-Assessment; D011795:Surveys and Questionnaires; D014850:Waiting Lists
keywords: Internet therapy; Web-based intervention; anxiety disorders; outpatients; phobias; phobic disorders; randomized controlled trial