How is PTA (Pure Tone Average) calculated?

The Pure Tone Average (PTA) is a common measure used in audiometry to represent an individual's hearing sensitivity. It is specifically calculated by taking the average of hearing thresholds at three key frequencies: 500 Hz, 1000 Hz, and 2000 Hz. This frequency range is chosen because it encompasses the critical speech frequencies, which play a significant role in communication and understanding spoken language.

To find the PTA, you sum the hearing thresholds (in dB) at these three frequencies and divide by three. This method gives a weighted representation of how well a person can hear in the frequency range that is most relevant for everyday communication.

Thus, the calculation involves adding the levels of hearing loss at 500 Hz, 1000 Hz, and 2000 Hz, and dividing the total by three, leading to the correct answer being the formula: (500 + 1k + 2k) / 3. This focus on the specified frequencies makes PTA a vital tool for audiologists and hearing aid dispensers in diagnosing and managing hearing loss.