title: Observer variability in the assessment of CT coronary angiography and coronary artery calcium score: substudy of the Scottish COmputed Tomography of the HEART (SCOT-HEART) trial.
abstract: Observer variability can influence the assessment of CT coronary angiography (CTCA) and the subsequent diagnosis of angina pectoris due to coronary heart disease.
  
  
  
  We assessed 210 CTCAs from the Scottish COmputed Tomography of the HEART (SCOT-HEART) trial for intraobserver and interobserver variability. Calcium score, coronary angiography and image quality were evaluated. Coronary artery disease was defined as none (<10%), mild (10-49%), moderate (50-70%) and severe (>70%) luminal stenosis and classified as no (<10%), non-obstructive (10-70%) or obstructive (>70%) coronary artery disease. Post-CTCA diagnosis of angina pectoris due to coronary heart disease was classified as yes, probable, unlikely or no.
  
  
  
  Patients had a mean body mass index of 29 (28, 30) kg/m(2), heart rate of 58 (57, 60)/min and 62% were men. Intraobserver and interobserver agreements for the presence or absence of coronary artery disease were excellent (95% agreement, κ 0.884 (0.817 to 0.951) and good (91%, 0.791 (0.703 to 0.879)). Intraobserver and interobserver agreement for the presence or absence of angina pectoris due to coronary heart disease were excellent (93%, 0.842 (0.918 to 0.755) and good (86%, 0.701 (0.799 to 0.603)), respectively. Observer variability of calcium score was excellent for calcium scores below 1000. More segments were categorised as uninterpretable with 64-multidetector compared to 320-multidetector CTCA (10.1% vs 2.6%, p<0.001) but there was no difference in observer variability.
  
  
  
  Multicentre multidetector CTCA has excellent agreement in patients under investigation for suspected angina due to coronary heart disease.
  
  
  
  NCT01149590.
authors.affiliation: University of Edinburgh/British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh , Edinburgh, Lothian , UK.
authors.forename: Michelle C
authors.initials: MC
authors.lastname: Williams
authors.affiliation: University of Edinburgh/British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh , Edinburgh, Lothian , UK.
authors.forename: Saroj K
authors.initials: SK
authors.lastname: Golay
authors.affiliation: University of Edinburgh/British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh , Edinburgh, Lothian , UK.
authors.forename: Amanda
authors.initials: A
authors.lastname: Hunter
authors.affiliation: Division of Cardiovascular and Diabetes Medicine , University of Dundee , Dundee , UK.
authors.forename: Jonathan R
authors.initials: JR
authors.lastname: Weir-McCall
authors.affiliation: University of Edinburgh/British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh , Edinburgh, Lothian , UK.
authors.forename: Lucja
authors.initials: L
authors.lastname: Mlynska
authors.affiliation: University of Edinburgh/British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh , Edinburgh, Lothian , UK ; Edinburgh Heart Centre, Royal Infirmary of Edinburgh , Edinburgh , UK.
authors.forename: Marc R
authors.initials: MR
authors.lastname: Dweck
authors.affiliation: Edinburgh Heart Centre, Royal Infirmary of Edinburgh , Edinburgh , UK.
authors.forename: Neal G
authors.initials: NG
authors.lastname: Uren
authors.affiliation: Borders General Hospital , Melrose , UK.
authors.forename: John H
authors.initials: JH
authors.lastname: Reid
authors.affiliation: Centre for Population Health Sciences, University of Edinburgh , Edinburgh , UK.
authors.forename: Steff C
authors.initials: SC
authors.lastname: Lewis
authors.affiliation: British Heart Foundation Glasgow Cardiovascular Research Centre, University of Glasgow , Glasgow , UK.
authors.forename: Colin
authors.initials: C
authors.lastname: Berry
authors.affiliation: University of Edinburgh/British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh , Edinburgh, Lothian , UK ; Clinical Research Imaging Centre, University of Edinburgh , Edinburgh , UK.
authors.forename: Edwin J R
authors.initials: EJ
authors.lastname: van Beek
authors.affiliation: Department of Radiology , Glasgow Royal Infirmary , Glasgow , UK.
authors.forename: Giles
authors.initials: G
authors.lastname: Roditi
authors.affiliation: University of Edinburgh/British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh , Edinburgh, Lothian , UK ; Edinburgh Heart Centre, Royal Infirmary of Edinburgh , Edinburgh , UK ; Clinical Research Imaging Centre, University of Edinburgh , Edinburgh , UK.
authors.forename: David E
authors.initials: DE
authors.lastname: Newby
authors.affiliation: Clinical Research Imaging Centre, University of Edinburgh , Edinburgh , UK.
authors.forename: Saeed
authors.initials: S
authors.lastname: Mirsadraee
keywords: CHEST PAIN CLINIC < CORONARY ARTERY DISEASE; CORONARY ARTERY DISEASE; CT SCANNING < IMAGING AND DIAGNOSTICS; IMAGING AND DIAGNOSTICS