title: Implementation of computerised physician order entry (CPOE) and picture archiving and communication systems (PACS) in the NHS: quantitative before and after study.
abstract: OBJECTIVE
  To assess the impact of components of the national programme for information technology (NPfIT) on measures of clinical and operational efficiency.
  
  
  METHODS
  Quasi-experimental controlled before and after study using routinely collected patient level data.
  
  
  METHODS
  Four NHS acute hospital trusts in England.
  
  
  METHODS
  Inpatient admissions and outpatient appointments, 2000-5.
  
  
  METHODS
  A system for ordering pathology tests and browsing results (computerised physician order entry, CPOE) and a system for requesting radiological examinations and displaying images (picture archiving and communications system, PACS).
  
  
  METHODS
  Requests per inpatient, outpatient, or day case patient for full blood count, urine culture and urea and electrolytes tests, and plain x ray film, computed tomography, and ultrasonography examinations.
  
  
  RESULTS
  CPOE was associated with a reduction in the proportion of outpatient appointments at which full blood count (odds ratio 0.25, 95% confidence interval 0.16 to 0.40), urea and electrolytes (0.55, 0.39 to 0.77), and urine culture (0.30, 0.17 to 0.51) tests were ordered, and at which full blood count tests were repeated (0.73, 0.53 to 0.99). Conversely, the same system was associated with an almost fourfold increase in the use of urea and electrolytes tests among day case patients (3.63, 1.66 to 7.94). PACS was associated with a reduction in repeat plain x ray films at outpatient appointments (0.62, 0.44 to 0.88) and a reduction in inpatient computed tomography (0.83, 0.70 to 0.98). Conversely, it was associated with increases in computed tomography requested at outpatient appointments (1.89, 1.26 to 2.84) and computed tomography repeated within 48 hours during an inpatient stay (2.18, 1.52 to 3.14).
  
  
  CONCLUSIONS
  CPOE and PACS were associated with both increases and reductions in tests and examinations. The magnitude of the changes is potentially important with respect to the efficiency of provision of health care. Better information about the impact of modern IT is required to enable healthcare organisations to manage implementation optimally.
authors.affiliation: Department of Social Medicine, University of Bristol.
authors.forename: Simon
authors.initials: S
authors.lastname: Collin
authors.forename: Barnaby C
authors.initials: BC
authors.lastname: Reeves
authors.forename: Jane
authors.initials: J
authors.lastname: Hendy
authors.forename: Naomi
authors.initials: N
authors.lastname: Fulop
authors.forename: Andrew
authors.initials: A
authors.lastname: Hutchings
authors.forename: Eugenia
authors.initials: E
authors.lastname: Priedane
mesh_terms: D000553:Ambulatory Care / Q000706:statistics & numerical data; D001071:Appointments and Schedules; D003631:Day Care, Medical / Q000706:statistics & numerical data; D003695:Delivery of Health Care / Q000592:standards*; D003955:Diagnostic Tests, Routine / Q000706:statistics & numerical data; D004739:England; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D050316:Medical Order Entry Systems / Q000458:organization & administration*; D017063:Outcome Assessment, Health Care; D011873:Radiology Information Systems / Q000458:organization & administration*; D012017:Referral and Consultation / Q000592:standards*