Hearing acuity was assessed using standard audiometric procedures, which required all participants to have a difference of less than 10 dB between ears at threshold and a hearing loss no greater than 25 dB at 500, 1,000, or 2,000 Hz. The ethnic composition in both groups was representative for the New York region, including several racial categories in each group (patients vs. controls: White 9/15, Black 6/3, Hispanic 4/3, Asian 2/1, more than one race or other, 2/1). The experimental protocol had been approved by the institutional review board and was undertaken with the understanding and written consent of each participant.
