Reliability of two methods for measurement of alveolar bone level in children

Objectives: To determine the intra- and interexaminer reliability of two methods (calliper and computerized images) for measuring the alveolar bone level on bitewing radiographs of pre-school children and to determine the extent to which one method can measure more sites. Methods: Standardized paediatric bitewings were analysed with either an image analysis program (ImageTool) or a digital calliper (Digimatic Caliper). With each method, radiographs were measured three times by three trained examiners. The differences in the number of sites measured with the two methods were assessed with McNemar's tests and kappa statistics. Reliability was assessed with paired t-tests, intraclass correlation coefficients (ICCs), Bland–Altman and survival-agreement plots. Results: The kappa statistics and McNemar's test indicated that examiners measured 14% fewer sites using ImageTool. Paired t-tests also demonstrated a statistically significant bias (range 0.11–0.23 mm) indicating larger measurements for this method, alt...