NATIONAL BOARD FOR CERTIFICATION IN HEARING
INSTRUMENT SCIENCES (NBS-HIS) STUDY READY
QUESTIONS AND ANSWERS BEST FOR EXAM
REVISION TO PASS 2025 EDITION.
1. Which audiometric pattern is most consistent with Otitis Media?
Correct Answer: BC = normal, AC = reverse slope, Type B tympanogram
Explanation: Otitis Media is a middle ear condition typically causing
conductive hearing loss with a flat (Type B) tympanogram, normal bone
conduction, and an air-bone gap showing a reverse slope.
2. What type of audiogram is typically seen in congenital cookie bite
hearing loss?
Correct Answer: Type A tympanogram with mid-frequency sensorineural loss
Explanation: Cookie bite audiograms show worse thresholds in mid
frequencies and often have normal tympanograms. This pattern is usually
congenital and may worsen over time.
3. A patient has single-sided deafness following mumps. What test result
supports this?
Correct Answer: Type A tympanogram, absent ipsilateral acoustic reflex
Explanation: Mumps can cause unilateral sensorineural hearing loss (aka
Single-Sided Deafness), often with a normal tympanogram but absent reflexes
due to neural damage.
4. Which description best matches sudden hearing loss?
, Correct Answer: ≥30 dB loss in 3 adjacent frequencies, rapid onset, often
unilateral
Explanation: Sudden Sensorineural Hearing Loss requires immediate
intervention with steroids or antivirals, ideally within 24–48 hours for optimal
recovery.
5. What pattern is associated with profound congenital loss?
Correct Answer: Corner audiogram, vibrotactile bone responses, poor
speech understanding
Explanation: These patients typically have no usable hearing in most
frequencies and are candidates for cochlear implants.
6. What causes acquired congenital loss, and what are typical findings?
Correct Answer: Maternal rubella in the first trimester, vibrotactile bone
responses, some residual speech frequency hearing
Explanation: Although not genetic, this loss is congenital and severe, but the
basilar membrane may still be partially responsive.
7. What audiological feature suggests a perforated tympanic membrane?
Correct Answer: Conductive loss, visible malleus pointing at 1:00 for right ear
Explanation: A perforation results in a conductive hearing loss and a Type B
tympanogram with large ECV.
8. What is the maximum conductive loss from absent TM and ossicular
chain?
INSTRUMENT SCIENCES (NBS-HIS) STUDY READY
QUESTIONS AND ANSWERS BEST FOR EXAM
REVISION TO PASS 2025 EDITION.
1. Which audiometric pattern is most consistent with Otitis Media?
Correct Answer: BC = normal, AC = reverse slope, Type B tympanogram
Explanation: Otitis Media is a middle ear condition typically causing
conductive hearing loss with a flat (Type B) tympanogram, normal bone
conduction, and an air-bone gap showing a reverse slope.
2. What type of audiogram is typically seen in congenital cookie bite
hearing loss?
Correct Answer: Type A tympanogram with mid-frequency sensorineural loss
Explanation: Cookie bite audiograms show worse thresholds in mid
frequencies and often have normal tympanograms. This pattern is usually
congenital and may worsen over time.
3. A patient has single-sided deafness following mumps. What test result
supports this?
Correct Answer: Type A tympanogram, absent ipsilateral acoustic reflex
Explanation: Mumps can cause unilateral sensorineural hearing loss (aka
Single-Sided Deafness), often with a normal tympanogram but absent reflexes
due to neural damage.
4. Which description best matches sudden hearing loss?
, Correct Answer: ≥30 dB loss in 3 adjacent frequencies, rapid onset, often
unilateral
Explanation: Sudden Sensorineural Hearing Loss requires immediate
intervention with steroids or antivirals, ideally within 24–48 hours for optimal
recovery.
5. What pattern is associated with profound congenital loss?
Correct Answer: Corner audiogram, vibrotactile bone responses, poor
speech understanding
Explanation: These patients typically have no usable hearing in most
frequencies and are candidates for cochlear implants.
6. What causes acquired congenital loss, and what are typical findings?
Correct Answer: Maternal rubella in the first trimester, vibrotactile bone
responses, some residual speech frequency hearing
Explanation: Although not genetic, this loss is congenital and severe, but the
basilar membrane may still be partially responsive.
7. What audiological feature suggests a perforated tympanic membrane?
Correct Answer: Conductive loss, visible malleus pointing at 1:00 for right ear
Explanation: A perforation results in a conductive hearing loss and a Type B
tympanogram with large ECV.
8. What is the maximum conductive loss from absent TM and ossicular
chain?
