The hearing screening process generally begins with a routine screening in preschool, kindergarten, grade 2, and grade 4. Children begin by practicing as a group, along with the hearing technician, as the tones are presented. The typical conditioned response is to raise one hand when a tone is initially heard, keeping it raised for the entire time that the sound is audible, and then lowering the hand when the tone can no longer be heard. For younger children, various forms of play audiometry are often used to achieve a desired response. Once the technician is confident in the students' responses, they are then screened individually.
The initial, or preliminary, screening is performed by presenting each ear with three pure tones at specific frequencies and decibels. If the child successfully responds to each tone, the technician records a passing result and the screening is complete. Should a child miss any presented tone, the technician makes a notation to follow up with a rescreen, and documents which tones were missed along with any other relevant information (noticeable congestion, cough, etc).
Rescreening
For children with a questionable initial screening result, rescreens are completed in approximately 4-6 weeks. Waiting a few weeks between screenings typically allows common conditions, which could potentially affect hearing ability, to resolve prior to attempting the screening process again. This would include conditions such as allergies, colds, ear infections, etc.
A rescreen, or intermediate screening, is performed by presenting each ear with six pure tones at specific frequencies and decibels. If the child successfully responds to each tone, the technician records a passing result and the screening is complete. Should a child miss any presented tone, a complete audiogram is initiated.
Audiogram
An audiogram is a detailed analysis of the child's hearing levels at that moment. During the audiogram process, the technician attempts to determine the child's hearing threshold, or the lowest level at which the child is able to reliably detect the tone at each frequency.
Air conduction thresholds are determined first for each ear. Air conduction is representative of what the child would hear during daily interactions.
Once air conduction levels are obtained, technicians then obtain and compare levels for bone conduction. Bone conduction is representative of what the inner ear is potentially capable of hearing without obstruction from fluid, wax, etc.
All results are reviewed according to MDHHS guidelines. Any child with screening results outside of these guidelines is referred for evaluation by a specialist.
Any child with final screening results outside of MDHHS guidelines is referred for evaluation by a specialist. Families receive a copy of the screening results along with a letter recommending follow up with a hearing specialist or primary care provider. The referral also includes a list of area hearing resources, guidelines for understanding the audiogram results, and a form for providers to document their examination and share their findings with the Health Department to complete the child's record.
Follow Up Letter
Records that are not updated with documentation of follow up are issued a second letter requesting assistance in updating the child's file. Please know that the Health Department is required by the MDHHS to follow up with each child who is referred to a specialist. Prompt return of the 'Physician / Audiologist Report' will help to prevent additional contacts for follow up.
Post Referral Screenings
Following a hearing referral, MDHHS guidelines require that two consecutive, passing audiograms be obtained before returning to the routine screening schedule. Those scheduled for follow up will automatically receive an audiogram the following year, until either 2 consecutive passing results are obtained, or technicians are no longer able to reasonably reach out to the child or family.