title: Collaborative care for pain results in both symptom improvement and sustained reduction of pain and depression.
abstract: OBJECTIVE
  Traditional analytic approaches may oversimplify the mechanisms by which interventions effect change. Transition probability models can quantify both symptom improvement and sustained reduction in symptoms. We sought to quantify transition probabilities between higher and lower states for four outcome variables and to compare two treatment arms with respect to these transitions.
  
  
  METHODS
  Secondary analysis of a year-long collaborative care intervention for chronic musculoskeletal pain in veterans. Forty-two clinicians were randomized to intervention or treatment as usual (TAU), with 401 patients nested within clinician. The outcome variables, pain intensity, pain interference, depression and disability scores were dichotomized (lower/higher). Probabilities of symptom improvement (transitioning from higher to lower) or sustained reduction (remaining lower) were compared between intervention and TAU groups at 0- to 3-, 3- to 6- and 6- to 12-month intervals. General estimating equations quantified the effect of the intervention on transitions.
  
  
  RESULTS
  In adjusted models, the intervention group showed about 1.5 times greater odds of both symptom improvement and sustained reduction compared to TAU, for all the outcomes except disability.
  
  
  CONCLUSIONS
  Despite no formal relapse prevention program, intervention patients were more likely than TAU patients to experience continued relief from depression and pain. Collaborative care interventions may provide benefits beyond just symptom reduction.
authors.affiliation: Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA 98195, USA; Geriatric Research, Education, and Clinical Center, Puget Sound VA Medical Center, Seattle, WA 98108, USA. Electronic address: sthielke@u.washington.edu.
authors.forename: Stephen
authors.initials: S
authors.lastname: Thielke
authors.affiliation: Portland Center to Improve Veteran Involvement in Care, Portland, OR 97239, USA; Department of Psychiatry, Oregon Health and Science University, Portland, OR 97239, USA.
authors.forename: Kathryn
authors.initials: K
authors.lastname: Corson
authors.affiliation: Portland Center to Improve Veteran Involvement in Care, Portland, OR 97239, USA; Department of Psychiatry, Oregon Health and Science University, Portland, OR 97239, USA.
authors.forename: Steven K
authors.initials: SK
authors.lastname: Dobscha
mesh_terms: D000368:Aged; D059350:Chronic Pain / Q000628:therapy*; D003299:Cooperative Behavior; D019033:Delivery of Health Care, Integrated; D003863:Depression / Q000628:therapy*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D059352:Musculoskeletal Pain / Q000628:therapy*; D017063:Outcome Assessment, Health Care / Q000379:methods*; D016037:Single-Blind Method; D014728:Veterans
keywords: Collaborative; Pain; Relapse; Remission; Transition