Audition assessment using the NIH Toolbox.

The NIH Toolbox project has assembled measurement tools to assess a wide range of human perception and ability across the lifespan. As part of this initiative, a small but comprehensive battery of auditory tests has been assembled. The main tool of this battery, pure-tone thresholds, measures the ability of people to hear at specific frequencies. Pure-tone thresholds have long been considered the "gold standard" of auditory testing, and are normally obtained in a clinical setting by highly trained audiologists. For the purposes of the Toolbox project, an automated procedure (NIH Toolbox Threshold Hearing Test) was developed that allows nonspecialists to administer the test reliably. Three supplemental auditory tests are also included in the Toolbox auditory test battery: assessment of middle-ear function (tympanometry), speech perception in noise (the NIH Toolbox Words-in-Noise Test), and self-assessment of hearing impairment (the NIH Toolbox Hearing Handicap Inventory Ages 18-64 and the NIH Toolbox Hearing Handicap Inventory Ages 64+). Tympanometry can help differentiate conductive from sensorineural pathology. The NIH Toolbox Words-in-Noise Test measures a listener's ability to perceive words in noisy situations. This ability is not necessarily predicted by a person's pure-tone thresholds; some people with normal hearing have difficulty extracting meaning from speech sounds heard in a noisy context. The NIH Toolbox Hearing Handicap Inventory focuses on how a person's perceived hearing status affects daily life. The test was constructed to include emotional and social/situational subscales, with specific questions about how hearing impairment may affect one's emotional state or limit participation in specific activities. The 4 auditory tests included in the Toolbox auditory test battery cover a range of auditory abilities and provide a snapshot of a participant's auditory capacity.