Concordance and consistency in the evaluation of diagnostic images of periapical tissue in endodontics

To estimate the degree of concordance and consistency in the radiographic and tomographic evaluation of the periapical area. A study of diagnostic tests was designed. Three blind evaluators analyzed radiographic images, which were selected at two different points in time. An oral radiologist and an endodontist determined the second observation moment. The degree of similarity and variability, concordance and consistency for each radiograph was set at 95% confidence. A Kappa coefficient (κ), for radiographic findings and a correlation coefficient of Lin (CCC) for tomographic measurements was established. 12 radiographies and 19 tomographs were evaluated. The intraobserver consistency determined a k= 1 (Almost Perfect) and a CCC from 0.42 to 0.95 (Poor to Substantial) for both observation times. For radiographies, the interobserver concordance did not show changes between the first and second observation. Values include a k= 0.56-0.80 (Moderate to Good) and a CCC with greater degree of agreement, after training, as follows: axial view: CCC 0.86, 95% of Confidence Interval (CI) 0.69-0.94, coronal view: CCC 0.90 95%CI 0.75-0.96, and sagittal view: CCC 0.96, 95%CI 0.90-0.98. The statistical tests estimated the consistency and concordance to observe radiographically and tomographically the periapical tissue in endodontics.