title: Interobserver variation in cell selection for DNA image cytometry.
abstract: OBJECTIVE
  To describe a systematic investigation of interobserver differences in interpretation of nuclear morphology in preparations of small cell lung cancer (SCLC).
  
  
  METHODS
  The screening/reviewing facility on the highly optimised microscope environment was used to individually tag 127 nuclei, chosen to reflect the spectrum of morphological appearances in nuclear preparations from three biopsy specimens of SCLC. Each nucleus was reviewed and labelled as control (lymphocyte), malignant or unsatisfactory by each of four observers. DNA histograms were plotted for each specimen using the nuclei identified as malignant by each participant. The histograms were compared in terms of identification of DNA stemlines and by calculation of a 5c exceeding rate (5cER).
  
  
  RESULTS
  Interobserver variation in assessment of morphology was seen in 55.1% of nuclei. Disagreement occurred most frequently in the malignant/unsatisfactory category. Differences in morphological classification had little influence on histogram assessment by means of visual inspection but did show an effect on 5cER.
  
  
  CONCLUSIONS
  There are significant interobserver differences in subjective assessment of nuclear morphology in cytometric preparations. This effect may seriously influence cytometric measurements.
authors.affiliation: Department of Pathology, University of Edinburgh.
authors.forename: F A
authors.initials: FA
authors.lastname: Carey
authors.forename: E
authors.initials: E
authors.lastname: Gray
authors.forename: M
authors.initials: M
authors.lastname: Salto-Tellez
authors.forename: C
authors.initials: C
authors.lastname: Kelly
authors.forename: R
authors.initials: R
authors.lastname: Dye
authors.forename: E
authors.initials: E
authors.lastname: Duvall
authors.forename: D
authors.initials: D
authors.lastname: Lamb
mesh_terms: D018288:Carcinoma, Small Cell / Q000235:genetics / Q000473:pathology*; D003584:Cytological Techniques; D004273:DNA, Neoplasm / Q000032:analysis*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008175:Lung Neoplasms / Q000235:genetics / Q000473:pathology*; D015588:Observer Variation; D011003:Ploidies
chemical_list: D004273:DNA, Neoplasm