American Academy of Audiology Clinical Practice Guidelines: Pediatric Amplification
American Academy of Audiology. (2013).
Reston (VA): American Academy of Audiology, 5-60.
This guideline provides recommendations for the selection, fitting, and verification, and outcomes assessment of amplification for children under the age of 18.
American Academy of Audiology
"Parent-to-parent support should be offered to families and caregivers of children with hearing loss" (Grade C Recommendation; p. 46).
"Monitor temporary threshold shift (TTS) if overamplification is suspected" (Grade B Recommendation; p. 22).
"For children older than about 6 years of age, paired-comparisons judgments may be used reliably to identify the optimal frequency response among a small set of alternatives. This assessment method may be more sensitive than speech perception testing, and is useful in identifying the way in which gain-frequency responses may be modified to meet individual needs" (Grade A and B Recommendation; p. 41).
"Behind-the-ear hearing aids (BTEs) are the style of choice while the child's ear is still growing.... [and] may provide appropriate coupling to a variety of assistive listening devices that may assist in educational and social settings" (p.18).
"Real-ear output response measurements with the use of real-ear to coupler difference (RECD) to correct threshold and resulting target data in the child's ear or 2 cc coupler measurements with measured or average RECD should be used for verification" (Grade B Recommendation; p. 34).
"All verification should be performed after the activation of any modern feedback suppression algorithm as it is a common process for manufacturers to limit accessible gains during the initialization process of the feedback suppression algorithm" (p. 26).
"In order to validate benefits and/or assist with fine-tuning, every child should receive an outcomes assessment after amplification is provided" (p. 41).
"Children with profound hearing loss by auditory brainstem response should not be excluded from receiving hearing aids prior to evaluation for a cochlear implant" (Grade D Recommendation; p. 13).
"Independent pediatric-focused and pediatric-validated prescriptive targets, normative data, and fitting methods that take into account the unique developmental and auditory needs of children should be used for pediatric hearing aid verification instead of manufacturer’s proprietary prescriptive approaches" (Grade A and B Recommendation; p. 32).
"Ongoing audiologic assessment and hearing aid verification are necessary to maintain audibility with the potential for fluctuation or progression of hearing loss, in addition to normal ear canal growth" (Grade C Recommendation; p. 46).
"In cases of bone conduction hearing aids, real-ear probe microphone measures cannot be conducted (when there is no acoustic signal in the ear canal), and the aided audiogram may be the most readily available verification option" (Grade D Recommendation; p. 40).
"Fine tuning and the accompanying verification and outcome assessment should have the goal of providing the least possible effect (distortion) that allows access to high frequency sound" (p. 26).
"Measurement of aided sound field thresholds should not be used as a method of hearing aid verification" (Grade B Recommendation; p. 39).
"De-activate or lock volume controls, or utilize wide dynamic range compression thereby eliminating the need for volume control manipulation for audibility and comfort" (p. 22).
"Use a validated, pediatric-focused prescriptive formula and account for the real-ear to coupler difference (RECD) when prescribing gain or output for a child in order to avoid overamplification" (Grade B, C, and D Recommendation; p. 22).
Amplitude compression should be employed and the prescription of gain should ensure that a range of input levels are sufficiently compressed to reduce sensitivity to loud sounds and restore speech audibility at low levels. "Compression characteristics should also minimize alteration of speech cues" (p. 25).
"Children with minimal hearing loss should be considered for remote microphone technology to improve signal to noise ratio" (p. 13).
"Tubing size, occlusion, and receiver placement are individual choices based on patient communication needs, ear canal dimensions, hearing loss severity and configuration, and patient preferences" (p. 18).
<p>Amplitude compression should be employed and the prescription of gain should ensure that a range of input levels are sufficiently compressed to reduce sensitivity to loud sounds and restore speech audibility at low levels (Grade B and C Recommendation).</p>
<p>"Selection of compression characteristics should also minimize alteration of speech cues. The generation of pediatric-focused target gains should be done with an independent prescriptive procedure" (Grade A and C Recommendation; p. 25).</p>
<p>"Multi-channel compression should be selected for the management of frequency specific audibility" (Grade C Recommendation; p 25).</p>
"Parental reports provide a reliable and sensitive method for evaluating alternative gain-frequency responses in hearing aids for [infants and young] children" (Grade B Recommendation; p. 41).
"Frequency lowering should not be prescribed until electroacoustic verification has revealed that high-frequency speech audibility cannot be restored through conventional means" (Grade A, B, and C Recommendation; p. 26).
"Use automatic feedback suppression in order to resolve feedback issues, either temporarily while awaiting new earmolds or permanently if needed to achieve the prescribed gains. Use feedback cancellation (which does not reduce the gain below the value that applies in the absence of feedback oscillation) in preference to feedback management systems that operate by reducing gain in one or more frequency regions, at one or more input levels, until feedback oscillation ceases" (p. 20).
"For infants, the only way to fully eliminate feedback may be to use an offsite/remote microphone. Caution must be used when considering this as a full time option because the child may not hear his/her own babbling/speech sounds if the microphone is not near the child's mouth" (p. 20).
<p>"There is evidence to suggest that frequency lowering may improve detection and recognition of high-frequency consonants for children with high-frequency hearing loss ranging from moderate to profound" (Grade B and C Recommendation; p. 26).</p>
<p>"There are also data that suggest acclimatization to frequency lowered amplification may increase both acceptance of and performance with a given frequency lowering technique" (Grade B and C Recommendation; p. 26).</p>
"Bilateral amplification is routinely recommended unless contraindicated" (Grade B Recommendation; p. 15). "If the unilateral hearing loss is aidable then a monaural fitting would be considered" (Grade B Recommendation; p. 15).
"A minimum of four to seven software adjustment bands (i.e., handles) should be selected for the digitally programmed hearing aid (Grade C Recommendation), .... [and] there should not be a disadvantage to increasing the number of bands beyond seven. The system also should allow sufficient flexibility to accommodate the child's growth, any progression or fluctuation in hearing thresholds, and any related changes to frequency shaping" (p. 25).
Contralateral Routing of Signal (CROS) may be considered for children with severe or profound unilateral hearing losses, depending on the child's age and ability to control their environment (Grade C Recommendation); however, "an FM system with a wireless remote microphone receiver coupled to the open, good ear may be preferable to a CROS configuration in classroom situations" (Grade B Recommendation; p. 16).
<p>"Outcome assessment should be carried out after introduction of new features in hearing aids.... [because] children's performance is affected by:</p>
<ul>
<li>variations in gain-frequency response slope of >3 dB/octave (Grade A and B Recommendation);</li>
<li>directionality of microphones;</li>
<li>presence or absence of noise reduction; and</li>
<li>applications of frequency compression or transposition in hearing aids" (p. 41).</li>
</ul>
Children with auditory neuropathy spectrum disorder are candidates for amplification, if speech at conversational levels is not easily audible due to poor hearing sensitivity (Grade B Recommendation). Trial amplification should be offered, "unless it can be established that the child is responsive to speech sounds at conversational levels without hearing aids. The hearing aid prescription should be altered as further information about hearing thresholds becomes available" (Grade B Recommendation; p. 13).
"Resources for financial support and funding to offset the cost of hearing aids should be provided, as concern for the cost of devices is often cited by parents as delaying the initiation of amplification" (Grade C Recommendation; p. 46).
"Extended high-frequency bandwidth (up to 9000 Hz) will improve audibility for sounds such as /s/ that represent an essential cue for the recognition of plural or possessive statements in the English language" (Grade B Recommendation; p. 26).
"Children with aidable unilateral hearing loss should be considered candidates for amplification due to evidence for potential developmental and academic delays" (Grade C Recommendation; p. 13)
Candidacy for bone conducted devices may include children with unilateral hearing losses (Grade B Recommendation) or children with permanent conductive hearing losses (Grade C Recommendation) only if anatomy is insufficient for coupling with air conduction hearing aids.
"The prescription of expansion in children should be done with the understanding that prioritizing comfort in quiet environments may have a negative effect on audibility of low level speech inputs" (Grade B and C Recommendation; p. 26).
"The impact of hearing aid signal processing and features such as directional microphones, digital noise reduction, feedback suppression and frequency lowering on audibility should be verified, if these features are determined to be appropriate.... If utilized with children, the impact of these features on audibility of speech should be evaluated during the verification process. If the signal processing strategy includes automatic activation of any features, verification of feature activation should be included" (pp. 33-34).
"Each child who receives a cochlear implant in one ear and who has residual hearing in the other ear should be fit with a hearing aid in that ear for providing bilateral stimulation" (Grade B Recommendation; p. 48). "Bimodal fitting should be provided even when residual hearing in the non-implanted ear is limited to frequencies below 500 Hz" (Grade B Recommendation, p. 48). "The hearing aid should be optimized with the cochlear implant by balancing loudness of sounds between ears" (Grade B Recommendation; p. 48).
"Referral to otolaryngology, ophthalmology and medical genetics should be provided for all children who are hard of hearing" (Grade D Recommendation; p. 46).
"Fitting of any frequency lowering algorithm should be accompanied by behavioral validation" (p. 26).
"Patient/family education and adjustment counseling (social and emotional support) should be provided as part of routine audiologic follow-up to ensure children and their parents and caregivers have the knowledge and assistance necessary to support consistent use of intervention strategies, including but not limited to hearing aid and other technology use [including tools and instructions to ensure proper function] and communication strategies as well as healthy psychosocial development" (Grade C Recommendation; p. 46).
"Compression limiting will provide superior sound quality as compared to hearing aids that limit maximum output through peak clipping" (Grade C Recommendation; p. 25).
"The response of the hearing aid should be measured for a variety of input levels to estimate the audibility of speech and ensure that the maximum output does not exceed prescribed levels" (Grade B Recommendation; p. 32).
"A standard real speech or a speech-like signal should be used when attempting verification of prescriptive methods for which the targets are based on speech inputs. That is, the preferred hearing aid verification method should include a test signal that produces an output similar to the output for a speech signal of the same input level.... [It may be] necessary to disable features that react differently to speech versus non-speech sounds, and the resulting measurement may then not be indicative of the hearing aid’s performance when the features are re-enabled" (Grade A Recommendation; p. 34).
"Referral for early intervention and educational services should occur in a timely manner in compliance with local, state and federal regulations" (Grade D Recommendation; p. 46).
"Approach venting cautiously in pediatric earmolds because of space limitations" (p. 20).
"Children with permanent conductive hearing loss should be fit with air conduction hearing aids when anatomically possible" (p. 13).
"Self-reports are sensitive to differences in hearing aid gains for school-aged children" (Grade A and B Recommendation; p. 42).
"Use pediatric ear hooks to promote retention of [behind-the-ear style hearing aids] BTEs" (p. 20) and "filtered ear hooks to ensure a smooth frequency response" (p. 20).
"All children with hearing loss should be considered candidates for FM use. When appropriately prescribed, FM systems will provide improvements in signal-to-noise ratio that are similar or superior to directional microphones" (Grade B Recommendation; p. 26).
<p>Candidates for amplification include</p>
<ul>
<li>children with aidable unilateral hearing loss (Grade C Recommendation);</li>
<li>children with minimal and mild hearing loss (Grade C Recommendation); and</li>
<li>children with auditory neuropathy spectrum disorder, if speech at conversational levels is not easily audible due to poor hearing sensitivity (Grade B Recommendation).</li>
</ul>
"On average, digital noise reduction is not expected to negatively impact speech recognition ability in children. The prescription of digital noise reduction should be done with the understanding that different implementations of this technology vary in their electroacoustic behavior and that prioritizing comfort or the acceptance of background noise may negatively impact speech audibility" (Grade B Recommendation; pp. 26-27).
<p>Several recommendations were provided pertaining to earmold fitting:</p>
<ul>
<li>"Provide a long, but comfortable earmold canal length to reduce the occlusion effect and to provide increased output in the ear canal due to decreased volume between the earmold and eardrum" (p. 20).</li>
<li>"Guard against reverse horns created by crimping the end of the sound channel in small earmolds" (p. 20).</li>
<li>"Be proactive regarding earmold replacement due to the child's growth" (p. 20).</li>
</ul>
"Utilize tamper resistant battery doors to decrease the likelihood of battery ingestion" (p. 22).
<p>"Full-time directional processing is not recommended. This feature may be recommended for children, although there are common listening environments in which directional technology is not desirable" (Grade A and C Recommendation; p. 26).</p>
<p>"Hearing aids that automatically switch between directional and omnidirectional modes depending on which mode produces the signal with the greater apparent signal-to-noise ratio should be considered" (Grade C Recommendation; p. 26).</p>
"Estimates of speech audibility using the Speech Intelligibility Index (SII) can be used to evaluate speech audibility for hearing aid fittings once primary verification has been completed through the verification software or computer programs" (Grade B and C Recommendation; p. 36).
"Identify prior skin reactions in order to minimize incidence of contact dermatitis with earmold impression and/or earmolds" (Grade B Recommendation; p. 23).
