title: Effect of psychiatric consultation models in primary care. A systematic review and meta-analysis of randomized clinical trials.
abstract: OBJECTIVE
  Psychiatric consultation in primary care is meant to enhance and improve treatment for mental disorder in that setting. An estimate of the effect for different conditions as well as identification of particularly effective elements is needed.
  
  
  METHODS
  Database search for randomized controlled trials (RCTs) on psychiatric consultation in primary care. Validity assessment and data extraction according to Cochrane criteria were performed by independent assessors in duplicate. Meta-analysis was performed.
  
  
  RESULTS
  Data were collected from 10 RCTs with a total of 3408 included patients with somatoform disorder or depressive disorder, which compared psychiatric consultation to care as usual (CAU). Meta-analysis irrespective of condition showed a weighted mean indicating a combined assessment of illness burden as outcome of psychiatric consultation, compared to CAU, of 0.313 (95% CI 0.190-0.437). The effect was especially large in somatoform disorder (0.614; 95% CI 0.206-1.022). RCTs in which after the consult, consultation advice was given by means of a consultation letter, showed a combined weighted mean effect size of 0.561 (95% CI 0.337-0.786), while studies not using such a letter showed a small effect of 0.210 (95% CI 0.102-0.319). Effects are highest on utilization of health care services with 0.507 (95% CI 0.305-0.708).
  
  
  CONCLUSIONS
  Psychiatric consultation in the primary care setting is effective in patients with somatoform and depressive disorder. Largest effects are seen in reduction of utilization of health care services.
authors.affiliation: Diagnosis and Treatment of Common Mental Disorders, Trimbos-Instituut/Netherlands Institute of Mental Health and Addiction, Utrecht, The Netherlands. cfeltz@trimbos.nl
authors.forename: Christina M
authors.initials: CM
authors.lastname: van der Feltz-Cornelis
authors.forename: Titus W D P
authors.initials: TW
authors.lastname: Van Os
authors.forename: Harm W J
authors.initials: HW
authors.lastname: Van Marwijk
authors.forename: Albert F G
authors.initials: AF
authors.lastname: Leentjens
mesh_terms: D015897:Comorbidity; D003299:Cooperative Behavior; D018592:Cross-Over Studies; D003866:Depressive Disorder / Q000175:diagnosis / Q000628:therapy; D005194:Family Practice; D006801:Humans; D033183:Interdisciplinary Communication; D001523:Mental Disorders / Q000175:diagnosis* / Q000628:therapy*; D010043:Outcome and Process Assessment, Health Care; D011320:Primary Health Care; D011570:Psychiatry; D016032:Randomized Controlled Trials as Topic; D012017:Referral and Consultation; D013001:Somatoform Disorders / Q000175:diagnosis / Q000628:therapy