Reproducibility of Clinical Grading of Tonsillar Size

Objective: To determine the reproducibility of the Brodsky grading scale and the modified 3-grade and 5-grade scales in reporting the size of the tonsils. Design: Retrospective review of 60 video recordings of tonsil examination by 12 independent observers with different clinical backgrounds and various levels of training. The sizes of the tonsils were graded using different grading scales. Setting: Tertiary care university hospital. Participants: The video recordings were chosen from an ongoing epidemiologic study of sleep-related breathing disorder in children in Hong Kong. Main Outcomes Measures: The intraobserver and interobserver reproducibility of each grading scale was determined using intraclass correlation. An intraclass correlation coefficient (ICC) exceeding 0.75 was set a priori to indicate an acceptable level of reliability. Results: The mean intraobserver ICCs for the Brodsky grading scale and the modified 3-grade and 5-grade scales were 0.858, 0.830, and 0.865, respectively. The mean interobserver ICCs for the Brodsky grading scale and the modified 3-grade and 5-grade scales were 0.763, 0.739, and 0.783, respectively. Conclusion: The Brodsky grading scale and the modified 5-grade scale achieved acceptable intraobserver and interobserver reproducibility.