title: Probabilistic model for prediction of angiographically defined obstructive coronary artery disease using electron beam computed tomography calcium score strata.
abstract: BACKGROUND
  Electron beam CT (EBCT) is an accurate, noninvasive method to detect and quantify coronary artery calcification, a marker of coronary artery disease (CAD). This investigation examined the accuracy of EBCT to detect obstructive CAD (> or =50% stenosis) and determined the optimal strata for quantity of coronary artery calcification to facilitate clinical decision-making.
  
  
  RESULTS
  Clinical research patients (n=213) were examined with coronary angiography and EBCT (angiography group), and 765 research participants were examined with only EBCT (nonangiography group). Of the angiography group, 53% had obstructive CAD. After adjustment for verification bias, the estimated sensitivity and specificity for calcium score > or =1 were 97.0% and 72.4%, respectively. Likelihood ratios for strata of calcium score associated with obstructive CAD were calculated in each sex and 2 age groups. Among those > or =50 years old, the same 4 strata of EBCT calcium scores were identified in each sex; likelihood ratios ranged from 0.03 (calcium score 0) to 12.85 (calcium score > or =200). The same 3 strata EBCT calcium scores were identified in each sex among those <50 years old; likelihood ratios ranged from 0.13 (calcium score 0) to 190 (calcium score > or =100).
  
  
  CONCLUSIONS
  A calcium score > or =200 among those > or =50 years old and calcium score > or =100 among those <50 years old provided strong evidence that patients of either sex had obstructive CAD. A calcium score of 0 provided strong evidence that patients > or =50 years old did not have obstructive CAD.
authors.affiliation: Department of Epidemiology, University of Michigan, Ann Arbor, USA.
authors.forename: L F
authors.initials: LF
authors.lastname: Bielak
authors.forename: J A
authors.initials: JA
authors.lastname: Rumberger
authors.forename: P F
authors.initials: PF
authors.lastname: Sheedy
authors.forename: R S
authors.initials: RS
authors.lastname: Schwartz
authors.forename: P A
authors.initials: PA
authors.lastname: Peyser
mesh_terms: D000328:Adult; D002114:Calcinosis; D002118:Calcium; D017023:Coronary Angiography; D003327:Coronary Disease / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D014057:Tomography, X-Ray Computed
chemical_list: D002118:Calcium