New Developments in Fitting Software for Children

It is crucial when fitting children to use appropriate hearing instrument settings and features to facilitate speech and language development and to give the child the best opportunities in life. The Junior Mode fitting software was developed with the help of the Phonak Pediatric Advisory Board (see Acknowledgements section) and the wider pediatric community to provide accurate, efficient, and holistic pediatric fittings.

The most recent research has been collated in order to provide evidence-based customizable software defaults specifically tailored to children. Additionally, printable counseling materials, the Junior Reports, aim to empower families, children, and teachers by providing individualized information about the child’s hearing loss, hearing system settings, as well as hints and tips on a wide range of relevant topics.

1. Why do we need pediatric fitting software?

Children with hearing loss. Hearing loss affects 1 to 3 infants per 1000 births.¹ This statistic increases when we include acquired or progressive hearing losses. Hearing loss can affect communication, cognition, behavior, social-emotional development, and academic potential.

With the introduction of universal newborn hearing screening (UNHS) and rapid advances in technology, the opportunity for improved long-term outcomes for hearing-impaired children has increased dramatically. Several studies have indicated that early diagnosis and intervention provides more positive outcomes for hearing-impaired children and their families.^2-4 These positive outcomes can be achieved only through early intervention, which ideally includes the use of high-quality hearing systems fit with pediatric-friendly software.

Matching technology to the needs of the individual child. According to the Pediatric Amplification Protocol⁵ set forth by the American Academy of Audiology (AAA):

The general goal of any hearing aid fitting is to provide a signal that makes soft, moderate and loud sounds audible but not uncomfortable and provides excellent sound quality in a variety of listening environments.⁵

This goal can be achieved using a recognized prescriptive formula, such as the Desired Sensation Level (DSL) or the National Acoustic Laboratories (NAL) fitting formulae, and verifying that prescription targets are met across a variety of input levels in an external test box.

However, in addition to meeting prescription targets, the needs of each child must be assessed individually so that appropriate hearing instrument features can be chosen. Prescription formulae are a starting point, but there are many other questions hearing care professionals need to consider when fitting a child. For example:

• Which features should I activate and which should be disabled to provide optimal audibility?
• How many programs should I give the child?
• When should I introduce a directional microphone?
• How does programming change as the child gets older?
• When should I introduce an FM system?
• What printed information should I give to the child, parents/caregivers, and teachers?

These questions can be challenging for both new and experienced pediatric hearing care professionals. The hearing instrument technology—including features, programs, and manual controls—must be matched to the needs of the child and their family.

The Junior Mode was developed in order to help answer these questions and to provide efficient, accurate, and tailored pediatric fittings, while taking into account the latest research and developments.

2. How does the Junior Mode help hearing care professionals?

The Junior Mode, developed with the help of the Phonak Pediatric Advisory Board, uses research-based evidence and takes a holistic approach to pediatric hearing care. The software is designed to allow for more accurate and efficient pediatric fittings, which should, in turn, provide more time for counseling and testing. One of the most important components of the new software involves a process that keeps members of the team updated using Junior Reports: counseling materials tailored to the needs of each child and their family. The software also takes into account the changing needs of children as they grow with three easy-to-access Junior Modes.

As an overview, the Junior Mode includes:

• Separate software defaults tailored for infants and toddlers (ages 0-4 years), schoolchildren (ages 5-8 years), and teens (ages 9-18 years);
• FM+M as the start-up program;
• DSLv5 as the default fitting formula (NAL-NL1 and proprietary formulae are also easily available as defaults);
• Useful time-saving pediatric defaults for the most important listening programs;
• Individual fitting philosophies are supported with customizable defaults;
• Printable tailored materials for parents, caregivers, and teachers;
• New features are available with each new software release.

3. What exactly are the evidence-based defaults?

Defaults for all Junior Modes (0-4, 5-8, 9-18 years). The need for evidence-based practice has grown over the past decade.⁶ The Junior Mode defaults were developed based on inputs from the international pediatric community, available research evidence, and the Phonak Pediatric Advisory Board.

The appropriate Junior Mode is automatically selected based on the child’s date of birth. If the developmental age of the child differs, the Junior Mode most suited to that child can easily be selected. All defaults can be clearly viewed in the software and can be customized depending on need. Junior defaults are applied depending on the features available within the selected hearing instrument model. For ease of understanding, defaults common across all Junior Modes will be discussed below, and user cases will be examined to show the differences between defaults for children ages 0-4, 5-8, and 9-18 years.

Start-up program: FM+M (FM+Speech in Quiet). Communication development in children with hearing loss is challenged by noise, reverberation, and distance, even with binaural amplification. FM systems are useful not only at school, but also in other situations, such as day care, home, and outdoor activities.⁷ The start-up program within the Junior Mode is FM+M by default, as long as the hearing instruments support FM. This allows easy access to FM solutions as the child’s instruments are always “FM Ready.”

In the past, clinicians have been concerned that the microphone (M) in the FM+M program was different from the microphone in the Calm Situations (Speech in Quiet) base program, especially for verification. However, the settings are now identical as can be seen in Figure 1. This means that optimized performance to prescription targets can be maintained regardless of which of these programs is used.

Default fitting formula: Desired Sensation Level (DSLv5). The default fitting formula for the Junior Mode is DSLv5, which is the most recent version released in 2006. The DSL prescription formula was originally validated to ensure that children—even those too young to respond to test signals—are given appropriate amplification. However, NAL-NL1 or proprietary formulae can also be easily chosen as a default. As long as the prescription formula has an evidence base, it is not important which formula is used.

A comprehensive discussion of the DSL method is offered by Scollie et al⁸ and an explanation of DSLv5 is offered by Moodie et al.⁹

SoundRecover (non-linear frequency compression) default: on. The aim of SoundRecover (non-linear frequency compression) is to take the high frequency sounds that the child is unable to hear, and compress them to a lower frequency region where the child can hear better. SoundRecover also seeks to give greater audibility of high frequency everyday sounds, such as birdsong or warning beeps. Importantly, SoundRecover uses a multichannel approach and incorporates a separate control for frequency compression only in the higher channel. This allows the lower frequencies to remain uncompressed to avoid vowel artefacts.^10,11

Stelmachowicz et al¹² demonstrated that children with mild to moderately severe hearing loss experience significantly greater difficulty with perception of the high frequency phonemes /s/ and /z/ while wearing their hearing instruments compared to the performance of children with normal hearing. In addition, they showed that discrimination of /s/ and /z/ was dependent upon adequate aided audibility up to at least 8000 Hz.

The provision of sufficient audibility for high frequency phonemes, such as /s/ and /z/, is critical for the development of speech and language (for example, /s/ is one of the most frequently occurring sounds in the English language). For this reason, SoundRecover is enabled by default, in the Junior Mode, in order to provide children with access to high frequency speech and environmental sounds.

What research evidence is available to use SoundRecover with children?

Several studies have shown benefits of using SoundRecover for both adults and older children. For example, Glista et al¹³ evaluated prototype multichannel non-linear frequency compression (SoundRecover) with 13 adults (aged 50-81 years) and 11 children (aged 6-17 years) with sloping high frequency hearing loss (ranging from moderately severe to profound). Several outcome measures were used, including speech sound detection, speech recognition, and self-reported preference measures. Results indicated that when SoundRecover was enabled, there was significant improvement of consonant and plural recognition, which are high frequency speech sounds. Importantly, vowel recognition did not change significantly, indicating that SoundRecover did not provide artifacts in the low frequencies. Glista et al attribute these benefits to the “increased audibility of additional high frequency energy, albeit presented in a lower frequency range, compared to the conventional hearing aid fittings.” An automatic pediatric fitting of SoundRecover, based on data collected from this study, also summarized in the November 2009 HR by Glista and colleagues,¹⁴ has been developed and implemented in all Junior Modes.

Is SoundRecover beneficial for children of all ages? Yes. SoundRecover “on” is the default for all three Junior Modes, for those hearing instruments that support SoundRecover.

As with many features, it is difficult to test SoundRecover on very young children due to a lack of test methods. However, the aim of SoundRecover is to provide access to important high frequency sounds for speech development, vital for infants. The Phonak Pediatric Advisory Board suggests using SoundRecover for infants as well as older children, with the usual monitoring and follow-up.

Patricia Roush, PhD, of the University of North Carolina at Chapelw Hill, has stated, “We were pleased to see interest in the development of hearing aids that have the capability to provide high frequency audibility for children. We are fitting it on children of all ages now and our experiences have generally been positive.” Likewise, Andrea Bohnert, MTA-F, a senior pediatric audiologist at University Mainz in Germany, states, “I have no reservations about using SoundRecover in newborns and children under one year of age…With SoundRecover, we expand the audible range and provide more information. I consider it problematic to reduce information for very young children [eg, with a noise-reduction algorithm]. However, I have no problem with providing more information, and we are ultimately able to do that with SoundRecover.”

Is SoundRecover beneficial for all levels of hearing loss? There is now not only research evidence showing the benefits of SoundRecover for those with moderately severe-to-profound hearing loss, but also preliminary results show the benefits of SoundRecover for children with mild-to-moderate hearing losses.

For example, Wolfe et al (“Initial experiences with non-linear frequency compression for children with mild to moderately severe hearing loss”; paper submitted) evaluated the benefits of SoundRecover for 16 children ages 5-13 years with mild-moderately severe sensorineural hearing losses. Results showed that none of the children objected to SoundRecover, and many immediately reported that they could understand speech better. These subjective findings were also supported by the UWO plural test scores, which showed a significant increase in speech scores with SoundRecover. Wolfe et al concluded that, due to the benefits, SoundRecover should be considered for children with mild-to-moderately severe hearing loss. A similar recommendation has been made by Richard Seewald, PhD, of the University of Western Ontario, who points out that “At this point, there is no indication that the benefits of SoundRecover are limited to any particular configuration or degree of hearing loss. What we’re trying to do, whether it be a mild, moderate, or profound hearing loss, is to bring sound into the audible range of the child.”

The iPFG 2.5 Junior Mode: Desktop Fitting Guide¹⁵ and a guide for verifying hearing instruments with SoundRecover can be found on the Phonak Web site.

DataLogging Default: enabled. DataLogging is always enabled by default in the Junior Mode, similar to the Standard Mode. DataLogging is an excellent tool for pediatric hearing care professionals as it helps to interpret reports from the child or parent and increases the efficiency of the fitting process.

Mute Default: off. The mute function of the hearing instrument is always off by default to avoid inadvertently turning the hearing instruments off.

Matching prescription targets: default. The Junior Mode aims to match prescription targets from first fit, making verification in an external test box more efficient. Thus, the defaults are occlusion control “off” (ie, no reduction of low frequency gain), acclimatization level “maximum” (to allow enough gain to reach targets), and default to the pediatric version of DSLv5 (rather than the adult version).

4. Use cases: Three different mode applications

In order to highlight the differences between three children of different age groups, three Junior Mode applications will be illustrated as case studies. Jessica, David, and Simon have exactly the same hearing loss and use the same hearing system (Figure 2):

• Jessica: Age 6 months, Junior Mode 0–4
• David: Age 5 years, Junior Mode 5–8
• Simon: Age 16 years, Junior Mode 9–18

Case 1: Jessica, 6 months old

Jessica’s hearing loss was detected after neonatal hearing screening. She was diagnosed with a mild-to-moderate hearing loss at 8 weeks and fitted with hearing instruments by 12 weeks. Her parents were good at accepting Jessica‘s hearing loss, and Jessica now attends nursery 2 days per week. Useful Junior Reports would include:

For Jessica’s family:

• Hearing system passport for parents
• SoundRecover information for parents
• Speech, language, and listening development (0-6 months)
• Diary of observations (0-4 years)
• Care and maintenance of the hearing system for parents
• General information for parents

Reports for Jessica’s nursery teachers:

• Hearing system passport for teachers
• SoundRecover information for teachers
• Care and maintenance of the hearing system for teachers

Case 2: David, 5 years old

David’s hearing loss was diagnosed at 12 months of age after parental concerns prompted testing. He was fit with hearing instruments within 2 weeks, and his parents were keen for as much information as possible. Both David and his parents accept the hearing loss and are open to hearing instruments. David attends a local mainstream school, where he also sees a speech and language therapist and teacher of the deaf. Useful Junior Reports would include:

For David’s family:

• Hearing system passport for parents
• SoundRecover information for parents
• Diary of observations (5-8 years)
• Care and maintenance of the hearing system for parents
• General information for parents

For David’s school teachers:

• Hearing system passport for teachers
• SoundRecover information for teachers
• Care and maintenance of the hearing system for teachers

Simon: 16 years

Simon had his hearing loss detected at 9 months, and was fitted with hearing instruments by 14 months. He takes college courses while attending high school, and plans to go to a university. He enjoys listening to his iPod, going to the cinema, and going out with friends. Useful Junior Reports would include:

For Simon:

• Hearing system passport for children
• SoundRecover information for children
• Diary of observations (9-18 years)
• Care and maintenance of the hearing system for children

For Simon’s family:

• Hearing system passport for parents
• SoundRecover information for parents
• Care and maintenance of the hearing system for parents
• General information for parents

For Simon’s college teachers:

• Hearing system passport for teachers
• SoundRecover information for teachers
• Care and maintenance of the hearing system for teachers

5. Can the defaults be customized?

Yes. All Junior defaults can be customized by the hearing care professional to match their fitting needs. Dollaghan¹⁶ points out that evidence-based practice should encompass not only external resources, such as peer-reviewed research published in respected journals, but should also be based on the clinician’s experience and expertise and the preferences of an informed parent or family member. In addition, McCreery,⁶ in his article on pediatric hearing aid verification, states that sometimes there is limited availability of research evidence due to the heterogeneity of hearing-impaired children who use hearing instruments and the fast pace of technological development. For this reason, all of the Junior Mode defaults are customizable so that defaults can easily be changed to match the needs of both the clinician and the child.

6. How are directional microphones fit to children addressed in the software?

Directional microphones are a controversial issue with differing expert opinions. Based on research, the default microphone mode for Junior Mode 0-4 is omnidirectional. The Phonak Pediatric Advisory Board recommends not using directional microphones for children under 5 years of age in order to maximize acoustic linguistic input and to aid localization.

For example, Akhtar¹⁷ suggests that children as young as 2 years of age access language through overhearing people around them in addition to direct communication. Directional microphones, in this context, could hinder access to speech, particularly if the child is not facing the speaker.

FM is the solution of choice for optimal hearing in noise for infants and young children. However, important new research from Ching et al¹⁸ has shed new light on the topic. They tested 27 hearing-impaired and normal-hearing children ages 10 months to 6 years and found that, if the child looks ahead, the signal-to-noise ratio (SNR) increases with directional microphones. There was a directional advantage of up to 3 dB SNR in different scenarios. Interestingly, they found that age does not affect the amount of time the child looks at the talker. Additionally, both normal-hearing and hearing-impaired children look at the talker more than 50% of the time with child-directed speech. Ching et al concluded that directional microphone technology does not significantly disadvantage children of any age.

However, it is important to counsel caregivers and professionals on making the most of the directional advantage by facing the child when talking and by teaching the child to look at the talker. It is clear that the use of directional microphones for infants and young children is controversial. As long as the discussion is still open, the Junior Mode default remains omnidirectional for Junior 0-4 based on the general consensus of the Phonak Pediatric Advisory Board. However, the default can be changed easily in the fitting software by clinicians who deem this the more prudent course.

In Junior Mode 5-8 and 9-18, the default microphone mode is Real Ear Sound in the Calm Situations program. Real Ear Sound restores pinna cues lost due to the microphone location effect of behind-the-ear (BTE) hearing instruments by utilizing advanced signal processing schemes.^19,20 Results from adult studies have shown that Real Ear Sound can improve localization abilities, particularly reducing front-back confusions (Phonak Field Study News, 2005; Phonak AG, Stafa, Switzerland, available at www.phonak.com).

In the Speech in Noise program, the default microphone is directional as research with older children has found directional microphones to be effective when listening in background noise. For example, Gravel et al²¹ found improved listening performance in noise with fixed directional microphones for two groups of children with hearing loss who were 4-6 years and 7-11 years. Directional microphones resulted in better performance at more difficult SNRs when compared to the omnidirectional condition.

Ricketts et al²¹ evaluated speech recognition in school-age children (ages 10-17) using directional microphones in a variety of simulated classroom environments. Directional microphones resulted in better speech recognition in noise when the desired speaker was in front of the child. Importantly, directional benefit in settings where the speaker was on the side or behind the student depended on the child’s ability to turn their head to the sound source of interest. It is therefore important for hearing care professionals to explain to the child and their caregivers about the situations where a directional microphone is useful.

In summary, based on the available evidence, the Junior Mode recommends that children older than 5 years can benefit from directional microphone technology in similar settings to adults when:

• The target is relatively close and to the front;
• The noise is primarily to the sides and the back;
• Reverberation is not excessive.²²

7. What are Junior Reports, and when and why are they useful?

The purpose of the Junior reports is to empower families and children by providing individualized information about the child’s hearing loss and hearing system settings, as well as in-depth information on a wide range of relevant topics. They also aim to facilitate good multidisciplinary teamwork in order to provide ongoing habilitation and support.

Separate reports are available for parents, teachers, and children, each tailored to their different needs. The comprehensive range of 22 Junior Reports cover a wide range of topics. The reports for teachers are designed to help understanding of hearing loss and hearing systems to allow effective teaching, particularly as the majority of hearing impaired children attend mainstream schools. The reports for children aim to give children ownership of their hearing loss, and are designed for the 9-18 age range. The reports developed for parents aim to provide understanding and practical tips for communicating with their hearing impaired child. To see a sample of all the Junior reports, visit www.phonak.com/pediatric_fitting.

By utilizing the reports, pediatric hearing care professionals can easily provide individualized information to parents, caregivers, teachers, and children. They can also keep the multidisciplinary team up-to-date with the child’s latest hearing test results and hearing instrument/FM settings. Further, the child’s name, date of birth, hearing instruments, and serial numbers are visible on each report for easy identification. Some of the Junior Reports include:

Hearing System Passport for parents/teachers/children. Provides personalized information on the child’s hearing loss, inserting the hearing instruments, child-specific hearing instrument/remote control instructions, FM systems and communication tips.

Communication tips and strategies for parents/children. Provides advice on communicating effectively and ways to help improve speech and language.

SoundRecover information (non-linear frequency compression) for parents/teachers/children. Written by Danielle Glista, MSc, of the University of Western Ontario, this report provides a clear explanation of SoundRecover, tips on listening checks, and some frequently asked questions.

FM System information for parents/teachers/children. Explains the benefits of FM technology and the use of FM systems at different ages, and gives details of the child’s specific FM system.

Speech, language, and listening development for parents. Provides parents and caregivers with a guide to listening and language development, as well as practical tips to help their child’s development. The easy-to-read informational sheets provide separate guides for children ages between 0-6 months, 6-12 months, 1-2 years, 2-3 years, and 3-4 years. Further references and resources are also available.

Diary of observations for parents/children. Provides a journal to help track progress, including any challenges experienced with the hearing instruments or FM system. It allows parents/children to get the most out of their audiology appointments and to monitor progress in a structured way.

Care and maintenance for parents/ teachers/children. Provides an easy-to-read flow chart explaining how to care for the hearing instruments and FM system. It covers earmolds, hearing aids, and listening checks, and also contains a trouble-shooting guide.

A guide to hearing loss and amplification technology for parents. Provides highly relevant general information for parents, covering topics such as hearing impairment, possible challenges/needs associated with different degrees of hearing loss, choosing the most suitable technology, FM systems, and cochlear implants.

8. Will the system help in my busy clinic?

The Junior Mode is designed to make fittings more efficient and accurate, and to improve understanding in order to provide more time for counseling. Several hearing care professionals specializing in pediatric fittings have expressed enthusiasm for the system and how it is important to recognize that adults and children require a different fitting approach. The programming is fast and efficient, and clinicians have particularly liked the separate software defaults for the different age groups, with the FM+M as the start-up program.

9. How does the software take into account the future of pediatric fittings?

The Junior Mode was first made available in October 2006 with iPFG 2.0. There have been six new releases since then, each with new features to respond to clinicians’ needs. We are already working on future developments to make the software even more user-friendly and valuable. Clinicians can also contact us with comments, suggestions, or questions.

10. Where can I get more information?

Two key benefits of the Junior Mode are the evidence-based defaults and the Junior reports. It is important that hearing care professionals are able to find out why certain defaults have been chosen. As a result, a Web site at www.phonak.com/pediatric_fitting provides a wealth of information, including samples of many of the items discussed above.

Summary

It is vital when fitting children to use suitable hearing instrument settings and features in order to provide access to speech and language and to give the child the best opportunities in life. The Junior Mode was developed with the help of the Phonak Pediatric Advisory Board and the wider pediatric community to provide accurate, efficient, and holistic pediatric fittings. The most recent research has been collated in order to provide evidence-based, customizable software defaults specifically tailored to children.

Additionally, the Junior Reports, printable via the Junior Mode, aim to empower families, children, and teachers by providing individualized information about the child’s hearing loss, hearing system settings, and in-depth information about a wide range of relevant topics. These tailor-made informational materials aim to facilitate good multidisciplinary teamwork in order to provide ongoing habilitation and support for children.

To take into account changing opinions and needs in the light of new research and feedback, additional features are added to the Junior Mode with each new software release.

Acknowledgements

The author thanks the Phonak Pediatric Advisory Board: Marlene Bagatto, John Bamford, Andrea Bohnert, Adrian Davis, Judith Gravel (deceased), Melody Harrison, Kevin Munro, Patricia Roush, Susan Scollie, Richard Seewald, Patricia Stelmachowicz, and Anne Marie Tharpe.

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