Clinical Practice Variation Needs to be Considered in Cost-Effectiveness Analyses: A Case Study of Patients with a Recent Transient Ischemic Attack or Minor Ischemic Stroke.
OBJECTIVE
The cost-effectiveness of clinical interventions is often assessed using current care as the comparator, with national guidelines as a proxy. However, this comparison is inadequate when clinical practice differs from guidelines, or when clinical practice differs between hospitals. We examined the degree of variation in the way patients with a recent transient ischemic attack (TIA) or minor ischemic stroke are assessed and used the results to illustrate the importance of investigating possible clinical practice variation, and the need to perform hospital-level cost-effectiveness analyses (CEAs) when variation exists.


METHODS
Semi-structured interviews were conducted with 16 vascular neurologists in hospitals throughout the Netherlands. Questions were asked about the use of initial and confirmatory diagnostic imaging tests to assess carotid stenosis in patients with a recent TIA or minor ischemic stroke, criteria to perform confirmatory tests, and criteria for treatment. We also performed hospital-level CEAs to illustrate the consequences of the observed diagnostic strategies in which the diagnostic test costs, sensitivity and specified were varied according to the local hospital conditions.


RESULTS
56 % (9/16) of the emergency units and 63 % (10/16) of the outpatient clinics use the initial and confirmatory diagnostic tests to assess carotid stenosis in accordance with the national guidelines. Of the hospitals studied, only one uses the recommended criteria for use of a confirmatory test, 38 % (6/16) follow the guidelines for treatment. The most cost-effective diagnostic test strategy differs between hospitals.


CONCLUSIONS
If important practice variation exists, hospital-level CEAs should be performed. These CEAs should include an assessment of the feasibility and costs of switching to a different strategy.
Institute of Health Policy and Management, Erasmus University Rotterdam, PO Box 1738, 3000 DR, Rotterdam, The Netherlands. buisman@bmg.eur.nl.|Institute for Medical Technology Assessment, Erasmus University Rotterdam, PO Box 1738, 3000 DR, Rotterdam, The Netherlands. buisman@bmg.eur.nl.
Leander R
LR
Buisman
Institute of Health Policy and Management, Erasmus University Rotterdam, PO Box 1738, 3000 DR, Rotterdam, The Netherlands.|Institute for Medical Technology Assessment, Erasmus University Rotterdam, PO Box 1738, 3000 DR, Rotterdam, The Netherlands.
Adriana J
AJ
Rijnsburger
Department of Neurology, Medical Spectrum Twente, PO Box 50000, 7500 KA, Enschede, The Netherlands.|Department of Neurology, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000 CA, Rotterdam, The Netherlands.
Heleen M
HM
den Hertog
Department of Radiology, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000 CA, Rotterdam, The Netherlands.
Aad
A
van der Lugt
Institute of Health Policy and Management, Erasmus University Rotterdam, PO Box 1738, 3000 DR, Rotterdam, The Netherlands.|Institute for Medical Technology Assessment, Erasmus University Rotterdam, PO Box 1738, 3000 DR, Rotterdam, The Netherlands.
William K
WK
Redekop
D016893:Carotid Stenosis / Q000175:diagnosis / Q000191:economics; D003362:Cost-Benefit Analysis / Q000379:methods*; D019983:Guideline Adherence / Q000191:economics / Q000706:statistics & numerical data; D017048:Health Care Costs; D006801:Humans; D007407:Interviews as Topic; D002546:Ischemic Attack, Transient / Q000175:diagnosis / Q000191:economics* / Q000628:therapy; D010818:Practice Patterns, Physicians' / Q000191:economics*; D020521:Stroke / Q000175:diagnosis / Q000191:economics* / Q000628:therapy; D011795:Surveys and Questionnaires