Whispered Voice Test at 2 Feet: Clinical Significance
The 2-foot distance in hearing testing is the standardized distance for performing the whispered voice test, which detects hearing loss at approximately 25-30 dB—the clinically meaningful threshold where soft speech becomes difficult to hear and communication problems begin to emerge. 1, 2
Diagnostic Performance at 2 Feet
The whispered voice test performed at 2 feet demonstrates excellent diagnostic accuracy with a positive likelihood ratio of 3.0-5.1 and a negative likelihood ratio of 0.03-0.52. 1 This means:
- The test has moderate ability to confirm hearing loss when positive
- The test has excellent ability to rule out hearing loss when negative (particularly valuable clinically) 1, 2
- Sensitivity reaches 86% or better for detecting hearing impairment 3
- Specificity is approximately 90% 3, 4
Clinical Threshold Detected
The 2-foot whispered voice test specifically targets the 25-30 dB hearing level, which represents: 1, 2
- The transition point from normal hearing (≤20 dB) to mild hearing impairment 5
- The threshold where soft speech and conversational difficulties begin 2
- Clinically significant hearing loss that benefits from intervention 2
- The average hearing loss seen in common conditions like otitis media with effusion (28 dB) 2
Children with hearing levels between 15-30 dB demonstrate significantly poorer cognitive, language, and reading skills compared to those with better hearing, emphasizing why this threshold matters clinically. 2
Comparison to Other Screening Methods
The whispered voice test at 2 feet performs comparably to more complex screening approaches: 1
- Nearly as accurate as detailed questionnaires (HHIE-S)
- Similar diagnostic accuracy to handheld audiometers for detecting hearing loss at 25-30 dB 1, 2
- More practical than finger rub or watch tick tests (which had wider confidence intervals and less validation) 1
- Simpler to perform than single-question screening while maintaining similar accuracy 2
Independent validation showed 100% concordance between observers for ears able to hear whispered voice at 2 feet, with 100% sensitivity and 84% specificity for detecting hearing impairment likely to benefit from hearing aid provision. 4
Critical Implementation Details
The 2-foot distance must be standardized to maintain consistency with the validated 25-30 dB threshold. 2 Key technical points:
- Distance standardization ensures reproducibility across examiners 3, 4
- Testing should occur in a quiet environment to minimize ambient noise interference 6
- The examiner stands 2 feet (approximately 60 cm) behind or to the side of the patient 3, 4
- The non-tested ear should be masked (typically by occluding the tragus) 3
Clinical Action Required
A failed whispered voice test at 2 feet requires formal audiometric evaluation to quantify the degree and type of hearing loss. 2 The screening test identifies risk but does not replace comprehensive audiometry, which remains the gold standard for:
- Measuring hearing thresholds at specific frequencies (250-8000 Hz) 5
- Differentiating conductive from sensorineural hearing loss 6, 5
- Determining appropriate intervention and monitoring changes over time 5
Quality of Life Impact
Hearing loss at the 25-30 dB threshold detected by the 2-foot whispered voice test has documented negative effects: 1
- Increased social isolation and emotional dysfunction in older adults 1
- Difficulty with speech discrimination and sound localization 1
- Impaired ability to function independently 1
- Reduced quality of life 1
The U.S. Preventive Services Task Force reviewed evidence showing that simple screening methods like the whispered voice test are useful in identifying persons at increased risk for hearing loss who would benefit from intervention. 1