In the 500 Hz pure-tone test: A-B gap were found in 102 ears(102/154, 66.2%) with the different hearing loss degree: 9 ears moderate, 17 ears moderate severe, 35 ears severe and 41 ears profound.

• 在500Hz处；102耳(66.；2%25)存在骨气导差；按听力损失程度分类:轻度0耳；中度9耳；中重度17耳；重度35耳；极重度41耳。