From roughly three to five years of age, when a child becomes quickly bored by visual reinforcement audiometry (VRA) and does not have the focus to complete a standard pure tone audiometry (PTA) test, conditioned play will be used during hearing testing. But what is a CPA test? How does it work and what do the results mean for your child?
Similar to a VRA, pure tones of varying frequency (Hz) and intensity (dB) are played to a child through earphones to measure hearing thresholds in each ear. Results are plotted on a graph and can be used to confirm hearing loss levels and thresholds, also leaving us with a picture of a hearing loss which can be summarised as mild, moderate, severe or profound. The results can be used to configure appropriate settings for hearing aids, cochlear implants or BAHAs.
Similar to a VRA test, one tester will sit in front of the child to engage them in play. They will explain to the child the process as simply as possible, that when a sound is heard, an action must be taken, for instance, each time a tone is played, a wooden peg is put in a container. The other tester will observe responses and control the stimuli (playing tones of differing frequency and intensity at random intervals). They will also record the results during the test. When the child places an item in the container upon hearing a sound, they will be given verbal praise and encouragement if correct. Similarly to an ABR test, the volume will start off high at the beginning of the test, so the child can become accustomed to the process, and then gradually be decreased as the test progresses. If conductive hearing loss is suspected, bone conduction pads may be attached behind the ears instead of earphones to see if there is an improved response using the same testing parameters.
Conditioned play audiometry is considered to be very accurate but much like VRA, reliability can fluctuate, especially during the early years and depending on a child’s level of engagement and focus during the test. The accuracy and reliability of a CPA is considered to be very high, even more so than a VRA which will likely be undertaken at an earlier age. Results can be used to configure optimum settings for BAHAs, cochlear implants or hearing aids.