title: Comparison between automated and manual measurements of carotid intima-media thickness in clinical practice.
abstract: OBJECTIVE
  The measurement of carotid intima-media thickness (cIMT) has been used as a marker of arterial wall disease. Manual measurements have been performed in most epidemiological studies, but, due to the introduction of new technologies, automated software has been increasingly used. This study aimed to compare manual versus automated cIMT measurements in common carotid (CC), bifurcation (BIF), and internal carotid (IC).
  
  
  METHODS
  Automated and manual cIMT measurements were performed online in 43 middle-aged females. Carotid segment measurements were compared by Bland-Altman plot and the variation and repeatability coefficients between observers were also determined for comparison.
  
  
  RESULTS
  The average timespan for manual measurements (57.30 s) were significantly higher than for automated measurements (2.52 s). There were no systematic errors between methods in any carotid segments. The variation coefficient was 5.54% to 6.34% for CC and BIF, 9.76% for IC, and absolute differences were 85% below 0.1 mm and 70% below 0.05 mm. Interobserver agreement showed no systematic error. The variation and the repeatability coefficients were better for the automated than manual measures.
  
  
  CONCLUSIONS
  Although both methods are reliable for cIMT measurements, the automated technique allows faster evaluation with lesser variability for all carotid segments currently used in atherosclerosis research.
authors.affiliation: Department of Internal Medicine, School of Medicine, Federal University of Minas Gerais (UFMG), Belo Horizonte, MG, Brazil.
authors.forename: Cláudia Maria Vilas
authors.initials: CM
authors.lastname: Freire
authors.forename: Antonio Luiz Pinho
authors.initials: AL
authors.lastname: Ribeiro
authors.forename: Felipe Batista Lima
authors.initials: FB
authors.lastname: Barbosa
authors.forename: Anelise Impelisiere
authors.initials: AI
authors.lastname: Nogueira
authors.forename: Maria Cristina Costa
authors.initials: MC
authors.lastname: de Almeida
authors.forename: Márcia Melo
authors.initials: MM
authors.lastname: Barbosa
authors.forename: Angela Maria Quintão
authors.initials: AM
authors.lastname: Lana
authors.forename: Ana Cristina Simões
authors.initials: AC
authors.lastname: e Silva
authors.forename: Antônio
authors.initials: A
authors.lastname: Ribeiro-Oliveira
mesh_terms: D000328:Adult; D057205:Automation, Laboratory; D017536:Carotid Artery, Common / Q000000981:diagnostic imaging*; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008875:Middle Aged; D015588:Observer Variation; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D017539:Tunica Intima / Q000648:ultrastructure*; D017540:Tunica Media / Q000000981:diagnostic imaging*; D014463:Ultrasonography