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An Audiogram and a Word-Recognition Score: Why They Answer Different Questions

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By DrBaba.com Health Research Team

A hearing report usually contains two kinds of results, and they are not interchangeable. The audiogram asks how softly a tone can be played and still be detected at each pitch. The word-recognition score asks something different: when speech is presented, what percentage of the words can you repeat correctly? One is about detecting sound. The other is about recognizing speech. The American Speech-Language-Hearing Association (ASHA) says accurate diagnosis depends on an audiologist interpreting a whole test battery in the context of your history, so neither number should be read alone.

What is each measure actually asking?

The audiogram: can you detect the tone?

Pure-tone audiometry is a behavioral test of hearing sensitivity. According to ASHA, results are plotted on an audiogram with sound frequency on the horizontal axis and sound intensity on the vertical axis, and the right and left ears are plotted separately. A threshold is the lowest intensity, in decibels, at which a given frequency is perceived 50% of the time. Thresholds are typically measured from 250 Hz to 8000 Hz.

Thresholds are then described by degree. ASHA presents one commonly used scale in decibels of hearing level (dB HL):

  • Normal: -10 to 15
  • Slight: 16 to 25
  • Mild: 26 to 40
  • Moderate: 41 to 55
  • Moderately severe: 56 to 70
  • Severe: 71 to 90
  • Profound: 91 and above

The shape of the line across frequencies is called the configuration. A flat configuration means about the same amount of loss at low and high pitches. A sloping one means the amount of loss changes across pitches.

The word-recognition score: can you tell the words apart?

ASHA describes speech audiometry as a way to evaluate speech perception ability as well as hearing sensitivity, which is why a report includes both kinds of results. Word-recognition scores are obtained for each ear using phonetically balanced one-syllable words and are expressed as a percent correct. Recorded presentation is the preferred method because it standardizes the word list and the speaker. If a live voice was used instead, ASHA says that should be noted in the results.

Speech testing also includes thresholds, which are easy to confuse with the percent score. A speech detection threshold is the softest level at which speech is noticed 50% of the time. A speech recognition threshold is the softest level at which about half of the speech material, typically two-syllable words, is correctly repeated. ASHA notes that detection is expected to be roughly 5 to 10 dB better than recognition, because recognition requires hearing and identifying the signal, not just noticing it.

What does a sample report legend look like?

The numbers below are invented to show the layout. They are not from a real person and are not a diagnosis. Real reports vary by clinic.

  • Frequency (Hz): the pitch of the tone, from low to high. Sample: 250, 500, 1000, 2000, 4000, 8000.
  • Threshold (dB HL): the softest level heard at that pitch, per ear. Sample right ear: 15, 15, 20, 30, 45, 55.
  • Speech level (dB HL): how loud the words were played. Sample: 65. A percent score is tied to the level at which it was obtained, so ask what the level was.
  • Recognition score (%): the share of words repeated correctly, per ear. Sample: 92% right ear.
  • Audiologist interpretation: the written summary that combines the results with your history. This is the part that carries clinical meaning.

Reading the invented thresholds against ASHA’s scale, 15 dB falls in the normal range and 45 dB in the moderate range. That is the same ear at different pitches, which is what “configuration” describes. The 92% is a separate result that answers a separate question, and neither set of numbers can be used to diagnose anything on its own.

Why can the two results seem to disagree?

Often they don’t. ASHA notes that in most cases there is a high correlation between speech thresholds and the pure-tone average, so speech thresholds serve as a cross-check on the audiogram. When the two disagree, ASHA says that points to inconsistent results, which can come from misunderstood instructions, equipment problems or other testing variables.

The word-recognition percentage is a different question from that cross-check. It tells you how well words were recognized at the level and in the conditions tested, and the audiologist interprets it alongside the thresholds.

What can a quiet-room test miss?

Much of everyday listening difficulty happens in noise, and a score from a quiet booth may not show it. ASHA states that results of speech testing in background noise may be quite different from results in quiet, which is why speech-in-noise testing exists. ASHA also describes cochlear synaptopathy, or “hidden hearing loss,” as a condition that a standard pure-tone exam does not identify and that often results in trouble understanding speech in noisy environments.

The practical point is that a normal-looking audiogram and real trouble in restaurants are not necessarily contradictory. If that describes you, tell the audiologist the specific situations. ASHA lists a noisy restaurant, a theater, large groups and riding in cars among the case-history details that help.

A quiet-room score is also not a forecast of how hearing aids will perform. In one hearing-center study of hearing-aid users, aided word recognition at 65 dB SPL was 10 to 20 percentage points below the maximum score measured with headphones, and the authors concluded that expectations should be adjusted accordingly. That is one study’s finding, not a rule for any individual.

What should you ask when you get the report?

  • Are the scores listed separately for each ear, and do the ears differ?
  • At what level were the words presented, and was it recorded or live voice?
  • Was anything tested in background noise? If not, would it be useful given my difficulties?
  • Do the speech thresholds agree with the audiogram?
  • Does anything here call for a medical referral or a follow-up test?
  • Is this a baseline I should compare future tests against?

The last question matters because ASHA lists establishing a baseline for future monitoring as one purpose of the assessment.

When should you not wait?

ASHA lists reasons a medical referral may be indicated, including ear pain or discomfort, active drainage from the ear, acute or chronic dizziness, and a history of sudden or rapidly progressive hearing loss in the previous 90 days. If your hearing changes suddenly, or you have any of those symptoms, seek prompt evaluation. Nothing on a hearing report is a reason to delay that in favor of a supplement.

What is a sensible next step?

If you already have a report, bring it and the questions above to the audiologist who performed the testing and ask them to walk you through each ear. If you have no report yet and are noticing difficulty, a comprehensive evaluation by an audiologist is the step that produces one.

This article is educational information, not individualized medical advice, and a sample report cannot be used to diagnose anything. See the site’s Medical Disclaimer.

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