Date amended:
Statements of Principles
Current RMA Instruments
Reasonable Hypothesis SOP
81 of 2019
Balance of Probabilities SOP
82 of 2019
Changes from previous Instruments


ICD Coding
  • ICD-9-CM Codes: 389.0
  • ICD-10-AM Codes: H90.2
Brief description

Conductive hearing loss results from a decrease in the sound level reaching the inner ear, due to a problem affecting the outer or middle ear.

Confirming the diagnosis

The diagnosis requires an audiogram, showing a permanent hearing loss, measured by air conduction, to at least the 25 decibel (dB) threshold level, at 500, 1000, 2000, 3000, 4000 or 6000 hertz (Hz), together with an air-bone gap in the affected ear of at least 10 dB at three of those frequencies, or a gap of at least 15 dB at any one of those frequencies.  An air-bone gap is present when a hearing threshold measured by masked bone conduction is better than that measured by air conduction, at the same frequency, in the same ear.  Hearing loss to at least the 25 decibel threshold level means a hearing threshold level of 25dB or below (i.e. 30, 35 etc).  A decrease from a previous reading by 25 dB (e.g. from 10 to 35 dB) is not required.

The audiogram should be performed by an Audiologist.  The relevant medical specialist is an Ear, Nose and Throat surgeon.

Additional diagnoses covered by SOP
  • Bilateral conductive hearing loss
  • Conductive deafness
  • Unilateral conductive hearing loss
Diagnoses which may be covered by SOP (further information required)
  • Mixed hearing loss – code and determine the conductive and sensorineural components separately
Conditions not covered by SOP
  • Central hearing loss - determine as part of the underlying brain injury or disease
  • Congenital deafness#                                 
  • Diplacusis#                                                      
  • Hyperacusis* 
  • Psychogenic / hysterical deafness / functional deafness#
  • Temporary or transient hearing loss – not a disease or injury
  • Presbyacusis* – covered by sensorineural hearing loss
  • Sensorineural/perceptive hearing loss*

* Another SOP applies

# Non-SOP condition

Clinical onset

This is a threshold diagnosis.  Clinical onset will date from the first audiogram to show a permanent hearing loss of the required level.  Hearing loss may be temporary.  An audiogram showing normal hearing (< 25 dB loss at the relevant frequencies), or no conductive component, rules out a clinical onset before that audiogram, even if there is a preceding abnormal audiogram.

Clinical worsening

A conductive hearing loss may remain stable or progress over time depending on cause.  Demonstration of clinical worsening would require an audiogram showing a decline in hearing from previously recorded levels, out of keeping with the normal course of the condition.