The use and reliability of SymNose for quantitative measurement of the nose and lip in unilateral cleft lip and palate patients

Background: It is essential to have a reliable assessment method in order to compare the results of cleft lip and palate surgery. In this study the computer-based program SymNose, a method for quantitative assessment of the nose and lip, will be assessed on usability and reliability. Objectives: Evaluation of this system, with which it is possible to determine quantitatively asymmetry of the face, after complete and incomplete unilateral cleft lip and palate surgery. SymNose has been extensively tested, and the system barriers have been documented. Methods: The symmetry of the nose and lip was measured twice in 50 six-year-old complete and incomplete unilateral cleft lip and palate patients by four observers. For the frontal view the asymmetry level of the nose and upper lip were evaluated and for the basal view the asymmetry level of the nose and nostrils were evaluated. Results: A mean interobserver reliability when tracing each image once or twice was 0.70 and 0.75, respectively. Tracing the photographs with two observers and four observers gave a mean interobserver score of 0.86 and 0.92, respectively. The mean intraobserver reliability varied between 0.80 and 0.84. Conclusion: SymNose is a practical and reliable tool for the retrospective assessment of large caseloads of two-dimensional photographs of cleft patients for research purposes. Moderate to high single interobserver reliability was found. For future research with SymNose reliable outcomes can be achieved by using the average outcomes of single tracings of two observers.