title: Influence of initial severity of depression on effectiveness of low intensity interventions: meta-analysis of individual patient data.
abstract: OBJECTIVE
  To assess how initial severity of depression affects the benefit derived from low intensity interventions for depression.
  
  
  METHODS
  Meta-analysis of individual patient data from 16 datasets comparing low intensity interventions with usual care.
  
  
  METHODS
  Primary care and community settings.
  
  
  METHODS
  2470 patients with depression.
  
  
  METHODS
  Low intensity interventions for depression (such as guided self help by means of written materials and limited professional support, and internet delivered interventions).
  
  
  METHODS
  Depression outcomes (measured with the Beck Depression Inventory or Center for Epidemiologic Studies Depression Scale), and the effect of initial depression severity on the effects of low intensity interventions.
  
  
  RESULTS
  Although patients were referred for low intensity interventions, many had moderate to severe depression at baseline. We found a significant interaction between baseline severity and treatment effect (coefficient -0.1 (95% CI -0.19 to -0.002)), suggesting that patients who are more severely depressed at baseline demonstrate larger treatment effects than those who are less severely depressed. However, the magnitude of the interaction (equivalent to an additional drop of around one point on the Beck Depression Inventory for a one standard deviation increase in initial severity) was small and may not be clinically significant.
  
  
  CONCLUSIONS
  The data suggest that patients with more severe depression at baseline show at least as much clinical benefit from low intensity interventions as less severely depressed patients and could usefully be offered these interventions as part of a stepped care model.
authors: NIHR School for Primary Care Research, Manchester Academic Health Science Centre, University of Manchester, Manchester M13 9PL, UK. peter.bower@manchester.ac.uk
authors: Peter
authors: P
authors: Bower
authors: Evangelos
authors: E
authors: Kontopantelis
authors: Alex
authors: A
authors: Sutton
authors: Tony
authors: T
authors: Kendrick
authors: David A
authors: DA
authors: Richards
authors: Simon
authors: S
authors: Gilbody
authors: Sarah
authors: S
authors: Knowles
authors: Pim
authors: P
authors: Cuijpers
authors: Gerhard
authors: G
authors: Andersson
authors: Helen
authors: H
authors: Christensen
authors: Björn
authors: B
authors: Meyer
authors: Marcus
authors: M
authors: Huibers
authors: Filip
authors: F
authors: Smit
authors: Annemieke
authors: A
authors: van Straten
authors: Lisanne
authors: L
authors: Warmerdam
authors: Michael
authors: M
authors: Barkham
authors: Linda
authors: L
authors: Bilich
authors: Karina
authors: K
authors: Lovell
authors: Emily Tung-Hsueh
authors: ET
authors: Liu
mesh_terms: D000328:Adult; D003866:Depressive Disorder / Q000523:psychology / Q000628:therapy*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D011613:Psychotherapy / Q000379:methods*; D012720:Severity of Illness Index; D006113:United Kingdom