What is required to confirm a permanent threshold shift?

To confirm a permanent threshold shift, it is essential to conduct a second audiometric test. This follow-up testing allows for a comparison with the initial audiometric results to determine if there has been a significant, sustained change in hearing capabilities. A permanent threshold shift is indicated when there is a notable decline in hearing thresholds, typically defined as a change of at least 10 dB at any frequency tested, across two separate audiometric evaluations conducted over a specified time frame.

While self-reports and documentation of previous thresholds can provide valuable context and background, they do not substitute for professional audiometric testing. Professional confirmation by a supervisor is important for oversight but does not provide the objective measurement necessary to confirm changes in hearing thresholds. Therefore, the correct approach for determining a permanent threshold shift relies on the evidence gathered from a second audiometric test, ensuring that the assessment is both reliable and valid.