Best Frequency for the Rinne Test
Use a 512 Hz tuning fork as the standard for performing the Rinne test in clinical practice. 1, 2
Recommended Frequency
The 512 Hz tuning fork should be the standard for screening patients for conductive hearing loss with the Rinne test. 2 While the 256 Hz fork is more sensitive for detecting conductive hearing loss, the 512 Hz fork provides the optimal balance between sensitivity and specificity, with fewer false-positive responses. 2
Evidence Supporting 512 Hz
The American Academy of Otolaryngology-Head and Neck Surgery recommends vibrating either a 256 Hz or 512 Hz tuning fork for the Rinne test, acknowledging both as acceptable options. 1
Research comparing multiple frequencies (256 Hz, 512 Hz, 1024 Hz, and 2048 Hz) found that 512 Hz minimizes false-positive responses while maintaining adequate sensitivity for clinically significant conductive hearing loss. 2
The 512 Hz fork demonstrates sensitivity ranging from 16% to 87% and specificity from 55% to 100% for detecting conductive hearing loss, with performance improving significantly when performed by experienced testers using masking. 3, 4
Why Not 256 Hz?
Although the 256 Hz fork is more sensitive than 512 Hz (sensitivity 43% to 91%, specificity 50% to 100%), it has a higher rate of false-positive results. 5, 3
The 256 Hz fork was found to be superior to 512 Hz in one study (p < 0.05), correctly identifying 87% of individuals with a 25 dB air-bone gap and 95% with a 30 dB gap. 5
However, the risk of vibrotactile responses (feeling rather than hearing the vibration) increases with lower frequency tuning forks, potentially leading to false-negative results. 6
Why Higher Frequencies Are Inadequate
Frequencies above 512 Hz become progressively less reliable for detecting conductive hearing loss. 6
At 1024 Hz, air-bone gaps of 45-50 dB are necessary to meet even a 75% correct detection criterion, and the 2048 Hz Rinne does not achieve even chance detection. 6
The number of negative (diagnostic) Rinnes decreases significantly as frequency increases above 256 Hz. 6
Clinical Performance Thresholds
The 512 Hz Rinne test can detect conductive hearing loss when the air-bone gap reaches approximately 15-20 dB, though reliability improves substantially at gaps of 25-30 dB or greater. 5, 3
The audiometric thresholds at which the Rinne test transitions from normal to abnormal range from 13 to 40 dB of conductive hearing loss across studies. 3
Critical Technique Considerations
Tester experience significantly impacts accuracy: experienced clinicians achieve much higher sensitivity than less-experienced testers. 4
Use masking of the contralateral ear when performing the test to improve reliability and prevent cross-hearing. 4
The loudness comparison method is superior to the threshold decay method (p < 0.01) for detecting air-bone gaps. 5
Strike the tuning fork on a covered elbow or knee (not a hard surface) to produce a pure tone without overtones. 1
Common Pitfalls to Avoid
Do not use tuning fork tests as a replacement for formal audiometry; they serve as screening tools only with sensitivity of approximately 77-85% and specificity of 85-94%. 1
Remove impacted cerumen prior to testing, as it can cause conductive hearing loss and lead to false-positive results. 1
Be aware that equivocal (+/-) results should be interpreted as indicating possible conductive loss to improve sensitivity. 4
Remember that tuning fork tests do not replace audiometric testing but provide valuable initial differentiation between conductive and sensorineural hearing loss. 1