Development and validation of an endoscopic ear surgery classification system

Objectives/HypothesisTo design and validate a classification system for endoscopic ear surgery. Study DesignValidation study. MethodsA classification system was devised that quantifies use of the endoscope during middle ear surgery. Otologic operative reports were reviewed by attending surgeons and trainees. A power analysis was performed to determine number of cases needed to review. The following categories were used: class 0 is defined by using the microscope only; class 1 describes the use of endoscope for inspection without dissection; and class 2 describes mixed use of the endoscope and the microscope. It is further subdivided into 2a and 2b, where the endoscope is used for less than 50% of dissection and more than 50% of dissection, respectively. Class 3 describes the use of the endoscope for the entire surgery. Fifty cases were reviewed by three attending otologic surgeons, one resident, and one medical student. ResultsWeighted Cohen's Kappa for inter-rater agreement between the two institutional surgeons was 0.79 (95% bias corrected [BC] confidence interval [CI]: 0.58-0.93). Agreement between the external surgeon and the two institutional surgeons was 0.77 (95% BC CI: 0.58-0.89) and 0.76 (95% BC CI: 0.57-0.88). Weighted Kappa between institutional surgeons and a resident was 0.73 (95% BC CI: 0.53-0.88) and 0.62 (95% BC CI: 0.38-0.80), and between institutional surgeons and a medical student was 0.75 (95% BC CI: 0.56-0.89) and 0.70 (95% BC CI: 0.49-0.85). ConclusionsThere was substantial inter-rater agreement. This classification system can be used as a simple and reliable tool to describe the extent to which an endoscope was used during ear surgery. Level of EvidenceNA. Laryngoscope, 128:967-970, 2018