An abbreviated impedance bridge technique for school screening.

The hearing of 539 children were screened by conventional audiometric techniques and an abbreviated form of impedance audiometry. Otoscopic examination and estimates of the cost to accurately detect hearing loss were used as critieria for comparing the two methods. The impedance technique detected 94% of hearing disorders, the audiometric, 24%. Projections of cost included a factor for number screened. These demonstrated that the impedance technique was less expensive and approached one-sixth the cost of the audiometric technique at a rate of 10,000 children per year. A routine application of the impedance technique in an ongoing hearing conservation program (N = 2712) supported the initial conclusion that it was more effective and more easily employable than audiometric screening. One child who passed impedance screening was shown to have a 50-dB sensorineural loss. It was concluded that an abbreviated form of impedance audiometry that includes a single high-frequency screening tone is the technique of choice for school screening.