THERE ARE two approaches to the measurement of bone-conduction thresholds. One approach searches for the absolute accuracy of the threshold determination and its reproducibility. This is a problem in audiology. The other approach searches for the clinical usefulness of any measurement of bone threshold (whether absolutely or relatively accurate). The clinical usefulness depends on which measure leads to the better diagnosis, and therewith the best decision for or against reconstructive middle ear surgery. We hold that these approaches can be independently studied and answered. The primary purpose of this report is to determine on a clinical basis the value of the sensorineural acuity level (SAL) as compared to the standard bone threshold (SB). In the literature there are many differing opinions and interpretations of observations about bone threshold testing. 1,2,4 Dr. Tillman 6 and Drs. Jerger and Jerger 3 have recently discussed the variables involved in bone threshold measurement from