Gardner-Robertson Hearing Class

Grades hearing in five classes from an audiogram (Gardner-Robertson 1988).

Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.

Example

Pure tone average
45 dB
Speech discrimination
80 %

Result: Gardner-Robertson class II - serviceable. Serviceable hearing. The two measures disagreed (pure tone average class II, discrimination class I); the poorer governs.

The tool opens with these values already filled in. Replace them with your own.

What the result means

Class I
Pure tone average 0-30 dB with 70-100% discrimination. Good to excellent.
Class II
31-50 dB with 50-69%. Serviceable.
Class III
51-90 dB with 5-49%. Non-serviceable.
Class IV / V
IV is 91 dB or more with 1-4%. V is hearing that cannot be tested, or 0% discrimination.
Which governs
The POORER of the two measures. That is why serviceable hearing needs 50 dB or better AND 50% or better, both rather than either.

What you enter

  • Pure tone average
  • Speech discrimination
  • Hearing not testable
How this is calculated

Gardner G, Robertson JH. Hearing preservation in unilateral acoustic neuroma surgery. Ann Otol Rhinol Laryngol. 1988;97(1):55-66. Read the source ↗

A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.

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Built by Clay Good. Source on GitHub.