An analysis of panel data. The impact of a psychiatric consultation letter on the expenditures and outcomes of care for patients with somatization disorder

Med Care. 1992 Sep;30(9):811-21.


In this study, the cost and health outcomes of a psychiatric consultation letter to primary care physicians caring for a sample of patients diagnosed with somatization disorder, a psychiatric condition associated with multiple, unexplained medical complaints, was assessed. To accommodate the small sample size of 73 patients, outcome effects were calculated using panel analysis. Study patients were randomized to a consultation or noconsultation group, and were repeatedly assessed at equal time intervals. Data were analyzed using parsimonious regression models derived from economic theory. During the 1-year follow-up period, a psychiatric consultation letter was associated with a 12% reduction in health care costs ($455 per patient within first year), with no evidence of deterioration in physical, mental, or general health. Less powerful t-test comparisons between treated and control groups lead to different conclusions. Reasons for these differences are discussed.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Arkansas
  • Costs and Cost Analysis
  • Female
  • Follow-Up Studies
  • Health Expenditures / statistics & numerical data*
  • Health Services Research
  • Humans
  • Male
  • Middle Aged
  • Models, Econometric*
  • Psychotherapy
  • Random Allocation
  • Referral and Consultation / economics*
  • Regression Analysis
  • Somatoform Disorders / economics*
  • Somatoform Disorders / therapy*
  • Treatment Outcome*