Which statement best defines a Standard Threshold Shift (STS)?

Which statement best defines a Standard Threshold Shift (STS)?

• A. A change in hearing threshold relative to baseline averaging 10 dB or more at 2,000, 3,000 and 4,000 Hz in either ear.
• B. A decrease in hearing sensitivity by 5 dB at 500 Hz.
• C. A temporary shift in hearing due to fatigue.
• D. An absolute threshold value at 1,000 Hz.

Answer: (A)

Standard Threshold Shift is a persistent change in a person’s hearing sensitivity, identified by comparing current hearing thresholds to the baseline audiogram. Specifically, if the average threshold at 2,000, 3,000, and 4,000 Hz in one ear has worsened by 10 dB or more relative to the baseline, that qualifies as a Standard Threshold Shift. These high-frequency sounds are where noise-induced hearing loss often shows up first, and averaging across multiple nearby frequencies helps account for normal testing variability at a single frequency. This measure is about a change relative to baseline, and it uses the same ear for the comparison. It’s not about a small change at 500 Hz, a temporary fatigue-related shift, or an absolute value at 1,000 Hz without reference to baseline.

Standard Threshold Shift is a persistent change in a person’s hearing sensitivity, identified by comparing current hearing thresholds to the baseline audiogram. Specifically, if the average threshold at 2,000, 3,000, and 4,000 Hz in one ear has worsened by 10 dB or more relative to the baseline, that qualifies as a Standard Threshold Shift. These high-frequency sounds are where noise-induced hearing loss often shows up first, and averaging across multiple nearby frequencies helps account for normal testing variability at a single frequency.

This measure is about a change relative to baseline, and it uses the same ear for the comparison. It’s not about a small change at 500 Hz, a temporary fatigue-related shift, or an absolute value at 1,000 Hz without reference to baseline.