title: Inter-observer variation in the interpretation of chest radiographs for pneumonia in community-acquired lower respiratory tract infections.
abstract: OBJECTIVE
  To assess inter-observer variation in the interpretation of chest radiographs of individuals with pneumonia versus those without pneumonia.
  
  
  METHODS
  Chest radiographs of out-patients with a lower respiratory tract infection (LRTI) were assessed for the presence of infiltrates by radiologists from three local hospitals and were reassessed by one university hospital radiologist. Various measures of inter-observer agreement were calculated.
  
  
  RESULTS
  The observed proportional agreement was 218 in 243 patients (89.7%). Kappa was 0.53 (moderate agreement) with a 95% confidence interval of 0.37 to 0.69. The observed positive agreement (59%) was much lower than for negative agreement (94%). Kappa was considerably lower, if chronic obstructive pulmonary disease was present (kappa = 0.20) or Streptococcus pneumoniae (kappa = -0.29) was the infective agent.
  
  
  CONCLUSIONS
  The overall inter-observer agreement adjusted for chance was moderate. Inter-observer agreement in cases with pneumonia was much worse than the agreement in negative (i.e. non-pneumonia) cases. A general practitioner's selection of patients with a higher chance of having pneumonia for chest radiography would thus not improve the observer agreement.
authors.affiliation: Department of General Practice, Care and Public Health Research Institute (Caphri), Maastricht University and University Hospital Maastricht, Maastricht, The Netherlands. rogier.hopstaken@hag.unimaas.nl
authors.forename: R M
authors.initials: RM
authors.lastname: Hopstaken
authors.forename: T
authors.initials: T
authors.lastname: Witbraad
authors.forename: J M A
authors.initials: JM
authors.lastname: van Engelshoven
authors.forename: G J
authors.initials: GJ
authors.lastname: Dinant
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017714:Community-Acquired Infections / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011014:Pneumonia / Q000000981:diagnostic imaging*; D011446:Prospective Studies; D011859:Radiography; D012141:Respiratory Tract Infections / Q000000981:diagnostic imaging*