title: Effect of usual source of care on depression among Medicare beneficiaries: an application of a simultaneous-equations model.
abstract: OBJECTIVE
  To investigate whether having a usual source of care (USOC) resulted in lower depression prevalence among the elderly.
  
  
  METHODS
  The 2001-2003 Medicare Current Beneficiaries Survey and 2002 Area Resource File.
  
  
  METHODS
  Twenty thousand four hundred and fifty-five community-dwelling person-years were identified for respondents aged 65+, covered by both Medicare Parts A and B in Medicare fee-for-service for a full year. USOC was defined by the question "Is there a particular medical person or a clinic you usually go to when you are sick or for advice about your health?" Ambulatory care use (ACU) was defined by having at least one physician office visit and/or hospital outpatient visit using Medicare claims. Depression was identified by a two-item screen (sadness and/or anhedonia). All measures were for the past 12 months. A simultaneous-equations (trivariate probit) model was estimated, adjusted for sampling weights and study design effects.
  
  
  RESULTS
  Based on the simultaneous-equations model, USOC is associated with 3.8 percent lower probability of having depression symptoms (p=.03). Also, it had a positive effect on having any ACU (p<.001). Having any ACU had no statistically significant effect on depression (p=.96).
  
  
  CONCLUSIONS
  USOC was associated with lower depression prevalence and higher realized access (ACU) among community-dwelling Medicare beneficiaries.
authors.affiliation: Centers for Disease Control and Prevention, Epidemiology and Applied Research Branch, Division of Cancer Prevention and Control, 4770 Buford Highway NE, Atlanta, GA, USA.
authors.forename: Chunyu
authors.initials: C
authors.lastname: Li
authors.forename: Andrew W
authors.initials: AW
authors.lastname: Dick
authors.forename: Kevin
authors.initials: K
authors.lastname: Fiscella
authors.forename: Yeates
authors.initials: Y
authors.lastname: Conwell
authors.forename: Bruce
authors.initials: B
authors.lastname: Friedman
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D003863:Depression / Q000175:diagnosis*; D005260:Female; D006297:Health Services Accessibility / Q000706:statistics & numerical data*; D006302:Health Services Research / Q000706:statistics & numerical data; D006304:Health Status; D006801:Humans; D008297:Male; D016344:Medicare Part A / Q000706:statistics & numerical data*; D016345:Medicare Part B / Q000706:statistics & numerical data*; D018802:Patient-Centered Care / Q000706:statistics & numerical data*; D012737:Sex Factors; D012959:Socioeconomic Factors; D014481:United States