title: Explaining variations in prescribing costs: results from a comparison of nursing home patients with matched pairs living in the community.
abstract: OBJECTIVE
  To examine and explain variations in prescribing costs associated with nursing home patients and patients matched by age and sex living in the community.
  
  
  METHODS
  A 12-month case control study.
  
  
  METHODS
  All nursing home residents over 65-years-old registered with nine general practices and patients matched with them for age and sex living in the community.
  
  
  METHODS
  Multivariate regression analysis of variations in monthly GP prescribing costs.
  
  
  RESULTS
  Multivariate regression models explaining cost variations in terms of the GP practice delivering care and patients' age and sex had little explanatory power (R(2)=0.07 for nursing home patients, R(2)=0.03 for matched pairs). A fuller model for nursing home patients only, incorporating the patient's Barthel score and initial diagnosis as additional explanatory variables, added little to the explanatory power of the model (R(2)=0.16).
  
  
  CONCLUSIONS
  The ability of the multivariate models used here to explain variations in prescribing costs among a group of elderly patients is poor. Adjusting weighted capitation formulae with respect to older patients to take account of such information or referring to it in negotiations on prescribing budgets would not appear to be warranted.
authors.affiliation: Trent Institute for Health Services Research, University of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, U.K. ciaran.o'neill@nottingham.ac.uk
authors.forename: C
authors.initials: C
authors.lastname: O'Neill
authors.forename: L
authors.initials: L
authors.lastname: Groom
authors.forename: A J
authors.initials: AJ
authors.lastname: Avery
authors.forename: D
authors.initials: D
authors.lastname: Boot
authors.forename: K
authors.initials: K
authors.lastname: Thornhill
mesh_terms: D000367:Age Factors; D000368:Aged; D016022:Case-Control Studies; D016527:Drug Costs; D011307:Drug Prescriptions / Q000191:economics*; D005260:Female; D006801:Humans; D008297:Male; D009735:Nursing Homes / Q000191:economics*; D012044:Regression Analysis; D012737:Sex Factors; D006113:United Kingdom