title: Request of acute phase markers in primary care in Spain.
abstract: OBJECTIVE
  To study the inter-practice variability in Spain--by institution, management, and regional characteristics--of the frequency and appropriateness of test requests made by primary care practitioners for acute phase markers.
  
  
  METHODS
  Observational cross-sectional study.
  
  
  METHODS
  One hundred forty-one clinical laboratories were invited to participate by providing the number of erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and complete blood count (CBC) tests requested by general practitioners. We calculated the ratio of test requests per 1000 inhabitants, ratios of related test requests, and variability index (90th percentile/10th percentile). We compared the results among the different areas according to their setting, location, and management.
  
  
  RESULTS
  We recruited 64 laboratories (14,846,065 inhabitants). There were almost twice as many ESR requests as CRP requests; the variability index for ESR was almost double that of CRP. Furthermore, the latter was underrequested in rural-urban areas compared with rural. The ESR/CBC and ESR/CRP ratios are lower in institutions with private management, and the number of ESR requested in institutions with private management are lower than that of public. The differences among Spanish regions were reported for ESR per 1000 inhabitants, ESR/CBC, and ESR/CRP.
  
  
  CONCLUSIONS
  There was significant variability in the requests made by primary care practitioners for patients' acute phase markers. Rates were influenced by geographic location, hospital setting, and institution management. ESR was inappropriately overrequested; strong efforts should be made to adjust the requests of ESR and to standardize the use of CRP measurement.
authors.affiliation: Hospital Universitario de San Juan de Alicante, Carretera Nacional 322. s/n 03550, San Juan, Alicante, Spain. E-mail: salinas_mar@gva.es.
authors.forename: Maria
authors.initials: M
authors.lastname: Salinas
authors.forename: Maite
authors.initials: M
authors.lastname: López-Garrigós
authors.forename: Emilio
authors.initials: E
authors.lastname: Flores
authors.forename: Joaquin
authors.initials: J
authors.lastname: Uris
authors.forename: Carlos
authors.initials: C
authors.lastname: Leiva-Salinas
mesh_terms: D015415:Biomarkers / Q000032:analysis; D001772:Blood Cell Count / Q000706:statistics & numerical data*; D001799:Blood Sedimentation; D002097:C-Reactive Protein / Q000032:analysis*; D064790:Clinical Laboratory Services / Q000706:statistics & numerical data; D003430:Cross-Sectional Studies; D055317:Evidence-Based Practice / Q000592:standards* / Q000706:statistics & numerical data; D019538:Health Care Surveys; D006801:Humans; D010818:Practice Patterns, Physicians' / Q000592:standards* / Q000706:statistics & numerical data; D011320:Primary Health Care / Q000379:methods / Q000592:standards* / Q000706:statistics & numerical data; D013030:Spain
chemical_list: D015415:Biomarkers; D002097:C-Reactive Protein