quantifying and responding to patient needs and expectations · embargo, no es un audiograma móvil...

J Am Acad Audiol 16:789–808 (2005)

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*University of Pittsburgh

Catherine V. Palmer, Ph.D., University of Pittsburgh, Department of Communication Science and Disorders, 4033 ForbesTower, Pittsburgh, PA 15260; Phone: 412-647-6089; Fax: 412-647-2455; E-mail: [email protected]

Quantifying and Responding to Patient Needsand Expectations

Catherine V. Palmer*

Abstract

Comprehensive audiometric testing serves as the cornerstone of adult hearingaid fittings for many clinicians. The data will serve to define the degree,configuration, and site of lesion of the hearing loss. The data will be used inprescriptive formula to preset the hearing aid and may be entered into probemicrophone or hearing aid test box equipment to provide verification targets.Clinicians are comfortable obtaining audiometric data, have an accepted wayof obtaining these data, and are comfortable discussing these data withpatients and other professionals. The patient, however, is not a walkingaudiogram and may bring all sorts of interesting nuances to the process.

Just as part of the clinician’s comfort with using audiometric data comesfrom the standard process of obtaining and reporting these data, the clinicianwho chooses to go beyond the audiogram in terms of data collection with apatient must have a means for gathering and quantifying additional information.The following case describes a method of obtaining and quantifying thepatient’s listening and communication needs. The case illustrates the use ofthese measures in recommending appropriate communication and safetysolutions.

Key Words: Assistive listening devices, communication needs, expectations,hearing aids, telephone, television

Abbreviations: ALD = assistive listening device; APHAB = Abbreviated Profileof Hearing Aid Benefit; AV = aversiveness; BN = background noise; EC = easeof communication; FM = frequency modulated; QuickSIN = Quick Speech inNoise Test; RV = reverberation; SNR = signal-to-noise ratio; STS-SPLITS =simulated telephone sensitivity—sound pressure level for inductive telephonesimulation; UCL = uncomfortable listening level

Sumario

La evaluación audiométrica integral es la piedra angular para muchos clíni-cos en la adaptación de auxiliares en adultos. Esta información servirá paradefinir el grado, la configuración y el sitio de la lesión de la pérdida auditiva.Los datos serán utilizados en una fórmula de prescripción para configurar elauxiliar auditivo y pueden ser introducidos en equipos de micrófono de sondao de caja de evaluación de audífonos, para conseguir mediciones de verifi-cación.Los clínicos se sienten a gusto obteniendo esta información audiométrica,disponen una forma aceptada para obtenerla y se sienten cómodos al discu-tir estos datos con pacientes y con otros profesionales. El paciente, sinembargo, no es un audiograma móvil y puede traer todo tipo de interesantesvariantes al proceso. Esta comodidad del clínico cuando utiliza informaciónaudiométrica, proviene de la forma estandarizada de obtener y reportar dichosdatos. Igualmente, el clínico que escoge ir más allá del audiograma al obtenerdatos del paciente, debe disponer de medios para recolectar y cuantificar lainformación adicional. El siguiente caso describe un método para obtener ycuantificar las necesidades de audición y comunicación del paciente. El casoilustra sobre el uso de estas medidas en la recomendación de solucionesapropiadas de seguridad y comunicación.

Comprehensive audiometric testingserves as the cornerstone of adulthearing aid fittings for many

clinicians.The results from this testing revealthe degree and configuration of hearing lossas well as recognition of monosyllabic wordsin quiet at a comfortable listening level. Inmost cases, the site of lesion can be definedfrom these findings, or further testing will beindicated to define the site of lesion. Basedon the results, the clinician will determine thestyle of hearing aid, which often isrecommended based on degree of hearingloss, and whether the individual needs one ortwo hearing aids. Special features includingmultiple channels and directionalmicrophones may be recommended based onthe configuration of the hearing loss and theresults of word-recognition testing,respectively. For instance, if the shape of theloss provides different average thresholdsacross three frequency areas on theaudiogram, a three-or-more-channel hearingaid may be needed to fine-tune the gain andcompression characteristics acrossfrequencies. If the hearing loss has a sharpslope into the high frequencies, the audiologistmay want a greater number of frequencychannels in order to shape the response andcontrol feedback. If a speech-in-noise task isemployed in the evaluation, the results maysuggest that the individual has greatdifficulty in noise even when sound ispresented audibly, and this may warrant theselection of directional microphones or otherspecial features. These decisions will bediscussed in detail later.

These same audiometric results providethe data used by current hearing aid fittingalgorithms (e.g., NAL-NL1 [Byrne et al, 2001];DSL[i/o] [Cornelisse et al, 1995]). Thresholdsare entered, and a series of mathematicalcalculations provide the clinician with thegain or output required for soft (50 dB SPL),moderate (65 dB SPL), and loud (85–90 dBSPL) input levels to match a prescriptivetarget. During verification, these samethresholds can be entered into real ear probemicrophone systems to provide a variety ofprescriptive target responses. Clinicians arecomfortable obtaining audiometric data, havean accepted way of obtaining these data, andare comfortable discussing these data withpatients and other professionals.The patient,however, is not a walking audiogram andmay bring all sorts of interesting nuances tothe process.

Just as part of the clinician’s comfortwith using audiometric data comes from thestandard process of obtaining and reportingthese data, the clinician who chooses to gobeyond the audiogram in terms of datacollection with a patient must have a meansfor gathering and quantifying additionalinformation. Consistent methods are essentialfor clinics with multiple practitioners andfrom a quality control perspective. Is it enoughthat clinicians interview patients and usethat information to inform their amplificationand treatment decisions, or is it necessary toimplement a more standard approach toinsure consistent, quality care? What doaudiologists need to ask in order to accuratelyand efficiently define the patient’s needs and

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Journal of the American Academy of Audiology/Volume 16, Number 10, 2005

Palabras Clave: Dispositivos de ayuda auditiva, necesidades de comunicación,expectativas, auxiliares auditivos, teléfono, televisión

Abreviaturas: ALD = dispositivo de ayuda auditiva; APHAB = Perfil Abreviadode Beneficio del Auxiliar Auditivo; AV = aversión; BN = ruido de fondo; EC =facilidad de comunicación; FM = frecuencia modulada; QuickSIN = Prueba deLenguaje Rápido en Ruido; RV = reverberación; SNR = tasa de señal-ruido;STS-SPLITS = sensibilidad simulada de teléfono – nivel de presión sonora parasimulación telefónica inductiva; UCL = nivel auditivo de molestia

Patient Needs and Expectations/Palmer

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expectations related to all hearing concerns?The following case is offered as an examplewhere a nondirected interview, widelyaccepted self-report techniques, andaudiometric data would not have lead toappropriate solutions for this patient.

PATIENT DESCRIPTION

Mrs. X is an 88-year-old woman whoarrived at the clinic with her daughter.

The patient was ambulatory with a cane andengaged in conversation with multiplerequests for repetition.The appointment waslisted as a hearing test with possible hearingaid discussion. The standard patient historyrevealed that Mrs. X’s chief complaint was nothearing well, and she indicated that she hadcome to the clinic to purchase a new hearingaid if needed. She indicated that her currenthearing aid did not always sound good whenthere were loud sounds, and it sometimessquealed. Her history was negative for earsurgery, ear pain or drainage, dizziness, andtinnitus. When asked about her generalhealth, Mrs. X indicated that she was not on

any medications and was in good health.Mrs. X indicated that she had purchased theone behind-the-ear hearing aid that she waswearing for her right ear approximately threeyears ago near where her daughter was livingat the time. She did not choose to go back tothat clinic since the daughter was no longerlocated there. The daughter revealed thatthey had traveled over 60 miles that morningto get to the clinic and that there were noaudiologists closer to where her mother wasliving. Otoscopic examination revealed clearear canals and an intact eardrum. Mrs. Xremoved her hearing aid so it could be cleanedand tested while she was having her hearingtest.

AUDIOMETRIC EVALUATION

Audiometric evaluation revealed a slopingmoderate to severe-to-profound

sensorineural hearing loss bilaterally (Figure1). Word recognition in quiet (recorded CIDW-22 female talker, 50 word list) at acomfortable listening level (100 dB HL and104 dB HL) produced scores of 32 and 30%

Figure 1. Audiometric results for patient X, an 88-year-old woman.

Table 1. Degrees of Signal-to-Noise Ratio Loss (SNR) and Resulting Recommendations

SNR Loss Degree of SNR Loss Recommendations

0–2 dB Normal/near normal As good as, or better than, normal-hearing individuals2–7 dB Mild SNR loss As good as many normal-hearing individuals7–15 dB Moderate SNR loss Directional microphones are recommended>15 dB Severe SNR loss Maximum SNR improvement is needed.

Consider an assistive listening device (e.g., FM system)

Source: Adapted from Etymotic Research, 2001.

in the right and left ear, respectively.Althoughthe signal-to-noise ratio (SNR) required toachieve 50% correct on the sentences in noise(QuickSIN; Etymotic Research, 2001) isroutinely evaluated when patients arepursuing amplification, the QuickSIN is notperformed if the individual displays poorword-recognition results in a quiet signalpresentation.The rationale for this is that thepatient is going to continue to have markeddifficulty in noise if he/she already hasdifficulty in quiet, and measurement will notinform the treatment recommendations.Conversely, there are individuals who doquite well in quiet but have greater difficultyin noise. It is not possible to predict this fromthe audiogram, so a speech-in-noise test isused to assist in recommending hearing aidfeatures (e.g., directional microphones) andassistive listening device solutions.

UNDERSTANDING SPEECH INNOISE

Table 1 provides the guidelines formatching technology with QuickSIN

results (Etymotic Research, 2001). Theserecommendations are published by EtymoticResearch and are based on a compilation ofdata from other studies revealing potentialdirectional microphone advantage.There arenot empirical data to match exact level ofSNR loss to technology recommendations.The clinician, however, may find theQuickSIN results to be a helpful counselingtool. If the patient is scoring at 7 dB SNR loss,it may be helpful to let the patient know thathe or she is functioning similarly to anormally hearing individual when the signalis presented at a comfortable level. Thismeans the patient needs amplification butthat he or she can sort out the signal andnoise fairly well without any remarkabletechnological manipulations. It is easy for apatient to lose sight of the fact that everyonehas difficulty hearing in noise some of thetime. This does not mean that an individualwith an SNR of less than 7 dB could notbenefit from a directional microphone; itsimply means that this technology may notbe a requirement for reasonable amplificationsuccess. If the patient’s score is greater than7 dB SNR, it is appropriate to indicate thathe or she has more difficulty than would beexpected once the signal has been madeaudible.

There are no data to indicate an exactlevel of SNR loss that will benefit most fromdirectional microphones and/or assistivelistening devices. Currently, these numberssimply support clinical decision making. Themore difficulty (greater the SNR), the moresignal enhancement the individual needs toperform well in noise. If directionalmicrophones are recommended, the clinicianneeds to take the time to train the user incorrect positioning within the listeningenvironment in order to take advantage of thesignal-to-noise ratio enhancement (Cord et al,2002). If a room is highly reverberant, thebenefits of a directional microphone will bediminished because the noise from behind theperson is reaching both microphones due toreflections in the reverberant environment.An assistive device will always provide thebest signal enhancement because themicrophone is located by the speaker andthe signal is delivered directly to the listenerovercoming any noise or distance problems.Users of assistive listening devices have to becomfortable placing the microphone in thedesired location whether that is by a lectureror on a companion at a restaurant. Thesuccess of either solution, directionalmicrophones or assistive devices, is dependenton patient education. Clinicians wouldwelcome well-controlled research that mightprovide predictive measures forrecommending these technologies.

In Mrs. X’s case, her word recognition inquiet was diminished to a point that it canbe assumed that her hearing in noise alsowould be compromised.According to the dataprovided by Thornton and Raffin (1978), Mrs.X’s true (95% confidence) word-recognitionscores could be anywhere between 16% and50% in the right ear and 14% and 48% in theleft ear. Even with this range, due to the poorreliability of word-recognition testing, it is safeto say that Mrs. X has poor recognition ofsingle words in quiet. Dubno et al (1995)provided data for the comparison of pure-tone average (PTA) and word recognition.According to these data, Mrs. X’s word-recognition results are disproportionatelylow compared to average results, meaningthat one would expect better (approximately44% or higher) word recognition given theaverage level of Mrs. X’s thresholds. Based onthe symmetry of the test results and the lackof any other signs and symptoms along withage, Mrs. X was not referred for further


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testing based on her disproportionately lowword-recognition scores.

SELF-REPORTED HEARING ABILITY

Patients are provided with a paper andpencil version of the Abbreviated Profile

of Hearing Aid Benefit (APHAB, Cox andAlexander, 1995) when they check in at thefront office. They complete the survey whilewaiting to be called in for their appointment.The APHAB is scored using a computerizedscoring tool by one of the front office staffwhile audiometric testing is being completedso the audiologist will have the APHABresults and audiometric results whendiscussing possible treatments with thepatient. Patients who currently wear hearingaid(s) are asked to complete the APHAB inthe “currently aided” condition. It is unlikelythat full-time users of amplification canrespond accurately to the APHAB statementsin the unaided condition because responseswould be based on the memory of how theyheard before they started using hearing aids.Therefore, Mrs. X was asked to respond to theAPHAB statements as if she were wearingher current hearing aid (right ear BTE). Theinstructions on the APHAB indicate that “ifyou have not experienced the situation wedescribe, try to think of a situation that youhave been in and respond for that situation.If you have no idea, leave that item blank.”

The computerized scoring program ofthe APHAB provides several pieces of data.There is a chart of the distribution of

responses (from A to G). The response foreach of the 24 items is noted. Ideally,responses will range from A to G without aparticular pattern. If all of the responses arein the middle, it generally means theindividual has put very little effort intoreading and answering the questionsaccurately. If the responses are all at the top(G) or all at the bottom (A) it means theindividual has not carefully read thequestions because a number of questions arepurposefully reversed and a consistentdemonstration of difficulty (similar to otherquestions) would require the individual toanswer on the opposite end of the scale forreversed questions.

Mrs. X responded to all of the APHABstatements, and her response patternindicated the majority of responses were oneither end of the scale (always or never), witha few responses toward the middle. Upon abrief inspection of individual items, it wasclear that Mrs. X perceived great difficulty inmost communication situations addressedon the APHAB (i.e., shopping, lectures, smallgroups, large groups, car, dinner table, offices,theaters, doctors’ offices, and worship) andhad little problem with loud (averse) sounds(i.e., sirens, traffic noise, smoke detector,running water, construction work, fire engines,and screeching tires). Her self-report regardingthe perception of loud sounds appears to bein contradiction to her earlier report duringthe case history.At that time she reported thather current hearing aid did not always soundgood when there were loud sounds. This

Figure 2. Abbreviated Profile of Hearing Aid Bene-fit (APHAB) results from the patient compared withnormal-hearing elderly individuals.

Figure 3. Abbreviated Profile of Hearing Aid Bene-fit (APHAB) results from the patient compared withusers of linear amplification.

apparent contradiction will be discussed laterin the paper.

COMPARISONS TO NORMATIVEDATA

The composite aided scores for the Ease ofCommunication (EC), Reverberation

(RV), Background Noise (BN), andAversiveness (AV) subscales are plotted inFigure 2. Mrs. X’s results are represented byA’s (aided condition), and the 5th to 95thpercentile for elderly individuals reportingno hearing loss are displayed for comparisonpurposes.These are normative data that allowcomparison of a patient to a representativegroup of people (e.g., other older adults). Basedon Figure 2, it would be correct to indicate thatMrs. X perceives more problems in quiet,reverberant, and noisy situations than 95% ofa population of older adults. Only about 5%of the population experience as little difficultyas she does with aversive sounds. Most of thepopulation experiences much more difficultywith these loud noises.

In Figure 3, Mrs. X’s results are comparedwith data from individuals of all ages wearinglinear amplification, which also can beconsidered a comparable population sinceMrs. X wears a linear hearing aid. Comparedto other users of linear technology, Mrs. X isat about the 95th percentile forcommunication situations. This means thatapproximately 95% of this populationperceives fewer problems than Mrs. X.Although this is acceptable performance (sheis within the population data between the 5thand 95th percentile), this is not ideal since sheis at the upper edge of what is considerednormal for this population. She is within the5th percentile for aversiveness (meaning thatshe has very little problem with aversivesounds). Only 5% of this population perceivesfewer problems than she does.

EVALUATING CURRENTAMPLIFICATION

If an individual currently uses amplification,electroacoustic and real ear aided response

measures are performed to evaluate theamplification the individual currently isusing. The treatment options includeknowledge of what the individual alreadyowns in case the current technology can beused in the recommended solution. Theassessment used for current amplification

includes measures that relate to the basicgoals of a hearing aid fitting: providingaudible and comfortable sound for soft,moderate, and loud input signals with lowdistortion (i.e., less than 10% total harmonicdistortion) across a variety of input levels.Additional hearing aid features are evaluated(e.g., telecoil, directional microphones, etc.).The worksheet presented in Appendix A(Palmer, 2003) provides the list of parametersmeasured. The worksheet presented inAppendix A has been filled out for Mrs. X, andthe measurement process will be describedbriefly below. A full description of this typeof evaluation can be found in Palmer (2003).

SIGNAL PROCESSING IN THECURRENT HEARING AID

Mrs. X is wearing an Oticon Personic 425hearing aid in her right ear.The hearing

aid is attached to a skeleton style acrylicearmold by an undamped earhook. ThePersonic provides linear gain (same gainregardless of input level) until limiting. Areview of the specifications for the Personic425 reveals “active output limiter” (or “AOL”)as the output limiting.This is a manufacturer-specific term. There is no easily availableelectroacoustic measure that will differentiatetypes of output limiting (peak clipping versusoutput compression limiting). A call to the


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Figure 4. Real-ear aided response measures for soft(50 dB SPL), moderate (65 dB SPL), and loud (85 dBSPL) input signals compared with the patients thresh-olds and uncomfortable loudness levels representedin dB SPL.


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company revealed that output compressionlimiting is employed. An input/output graphfrom the ANSI (1996) test verified a linearresponse through 70 dB input and thenoutput limiting with a maximum output ofapproximately 130 dB SPL. This hearing aidhas two potentiometers for responsemanipulation: UCL (uncomfortable loudnesslevel) and “AGram.” The UCL potentiometercontrols maximum output and was set to“full on” (allowing maximum output). The“AGram” control serves as a low-frequencytone control. The current setting providedmaximum gain for low frequencies.

REAL-EAR PROBE MICROPHONERESPONSE WITH THE CURRENT

HEARING AID

Real-ear aided response measures are usedto address the first three items on the

worksheet in Appendix A. The reliability andvalidity of real-ear aided response measureshave been established and repeatedlyreported in the literature (Hawkins andMueller, 1986; Dirks and Kincaid, 1987;Hawkins, 1987; Tecca et al, 1987; Killion andRevitt, 1993; Scollie et al, 1998). Theindividual’s thresholds are entered into thereal-ear probe microphone system, and thesystem converts these HL data to SPL datausing average conversions. The display (seeFigure 4) presents right-ear thresholds ascircles and UCL (either average or measuredif those have been entered) as asterisks. ForMrs. X, average UCLs were used. The plussigns reveal the DSL [i/o] (Cornelisse et al,1995) target for average input levels. Thetarget does not have to be used, but it isdisplayed. The three curves on the plotrepresent the results for a soft input (50 dBSPL), moderate input (65 dB SPL), and loudinput (85 dB SPL). A speechlike signal wasused to obtain these curves (Stelmachowicz etal, 1996; Scollie and Seewald, 2002).The curvefor the soft input should be at or slightly abovethreshold.The moderate input should be abovethreshold but below UCL, and the loud inputshould be above the moderate response butbelow UCL. As indicated on the worksheet inAppendix A, the hearing aid achieves thesegoals, although the loud input could providea higher output in the low frequencies.

These judgments must be made in thecontext of what is realistically achievable withthe individual’s hearing loss. For example,

soft and moderate sounds are not audible inthe higher frequencies, but given thresholdsof 85 to 100 dB SPL, there is no fitting that willachieve audibility at these levels, and there aredata to suggest that audibility will not beuseful to the patient at these levels (Turnerand Cunningham, 1999; Baer et al, 2002).Even if audibility could be achieved, it certainlywould cause sounds to be uncomfortably loud.It is within this context that bandwidth isexamined as well. For this patient, thebandwidth of this hearing aid is appropriate.In addition, there are no data to suggest “howaudible”a signal should be for an adult listener.Should soft be just above threshold; shouldmoderate be at the halfway point, and so forth?Currently, the rationale that the patient cannotuse a signal if it is not audible and will not usea signal that is uncomfortable are followed.David Pascoe said it eloquently, “although itis true that mere detection of a sound does notensure recognition. . . . It’s even more truethat without detection, the probabilities ofcorrect identification are greatly diminished”(Pascoe, 1989).

THE IMPORTANCE OF AUDIBILITY

The question of audibility has been fairlywell defined for the pediatric population.

Stelmachowicz et al (2000, 2002) provideconvincing data that for the child with littlelanguage context, audibility across a widebandwidth is essential for speechunderstanding. Adults may have differentrequirements and preferences than childrenbecause of previous listening experience andability to rely on context. Sousa (2000)compared the articulation index (an audibilitymeasure) after matching the hearing aid fittingto an NAL-R target to self-perceivedperformance after a year of use. Thecorrelations were very low, indicating thataudibility alone is not sufficient to produce self-perceived benefit. In fact, adults’ self-perceivedbenefit appears to decrease as audibilityincreases past a certain level (presumablycomfort; Leijon et al, 1990; Stelmachowicz etal, 1998). Discrepancies about just how audiblesound should be for the adult patient maystem in part from a lack of data related to therole of binaural summation (amplification inboth ears), and the use of signal summation(warble tone to broad-band stimuli) transformsfrom normal-hearing individuals.

Lindley et al (2001) reported loudness

growth data for both normal-hearing andmoderately hearing-impaired individuals.Thenormal listeners had the greatest loudnesssummation (from warbles to speech) forcomfortable level stimuli and less for soft andloud stimuli.For the hearing-impaired subjects,loudness summation was greatest for loudstimuli rather than for moderate stimuli. Aprediction of loudness summation from warbletones to speech is important because hearingaid fitting algorithms and verification arebased on tonal inputs, but the individual willbe listening to speech. Current hearing aidfitting algorithms are based on the expectedloudness summation of normal listeners. Asmore is understood about the damaged systemand its impact on perception, these assumptionsmay need to be modified. These findings mayhelp explain some dissatisfaction with varyingamounts of audibility even when the clinicianhas “met a target.”

Although data suggest that new hearingaid wearers adjust to newly audible soft soundsover time (Mueller and Powers, 2001), the datarelated to adaptation to loud sounds suggest thatadults do not experience increased tolerance(Schmitz, 1969; Walden et al, 1977; Berger andHagberg, 1982; Byrne and Dirks, 1986). Theclinician will want to verify that loud sounds arenot uncomfortable prior to the patient leavingthe hearing aid fitting. The data indicate thatthere should not be an expectation that the patientwill adjust to being uncomfortable,and further,thisdiscomfort may preclude use of the hearing aid.In fact,Kochkin (2003) reported that only 42% ofhearing aid users in his survey of approximately11,000 hearing aid users are satisfied regardingcomfort for loud sounds. When asked whatimprovements they would like to have in new

hearing aid technology,58% indicated that having“loud sounds be less painful” would be a highlydesirable improvement.

LOUDNESS JUDGMENTS WITH THECURRENT HEARING AID

As part of the assessment of currenttechnology, the patient’s response to loud

sounds is elicited to ensure that the currenthearing aid fitting is not uncomfortable. A 60dB SPL and 80 dB SPL broad-band speechsignal are provided,and the patient is asked torate each signal using the 7-point rating scalefrom Cox’s (1994) Contour Test (very soft touncomfortably loud).A rating of 3–5 for the 60dB SPL signal and a rating of 5–6 for the 80 dBSPL signal is the goal. If the rating is a 7 for the80 dB SPL signal, the gain for loud sounds orthe maximum output to ensure comfort for theindividual has to be decreased.Soft sounds arenot rated because this perception will changeover time since these are the sounds the patienthas not been hearing (Mueller and Powers,2001). Mrs. X rated the moderate sound as a 4and the loud sound as a 6.

SOUND QUALITY OF THE CURRENTHEARING AID

Sound quality is examined through anobjective measure and patient interview.

In taking the original history, the patientindicated that she did not like the sound of herhearing aid when there was loud sound aroundher.An electroacoustic analysis of her hearingaid with its current settings is displayed inFigure 5. This is the gain curve for an 85 dBinput signal. This test provides harmonicdistortion bars (not displayed on this figure)


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Figure 5. Electroacoustic analysis of the gain and fre-quency response of the hearing aid with a moderate(50 dB SPL) input signal. The dash/dot line illus-trates the response without a damped earhook, andthe dashed line illustrates the response with a dampedearhook.

Figure 6. Total harmonic distortion is illustratedby the bars along the x-axis and by percent on theright y-axis. The total harmonic distortion across fre-quency is less than 10%.


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that reached greater than 30% acrossfrequencies. Ten percent distortion isconsidered to be the greatest allowabledistortion for reasonable sound quality(Nielsen et al, 1990) and is easily achievablein hearing aids available today. Unlike theANSI (1996) recommendation, an input signalof 85 dB SPL is used in order to test theharmonic distortion of the hearing aid. Mosthearing aids have reasonably low distortion atthe ANSI input levels (60 to 70 dB SPL), andit is not until they are driven into saturationthat distortion is revealed. An 85 dB SPLsignal is a common input level at the hearingaid microphone including the user’s own voice.

The distortion measure is viewed in lightof the frequency/gain response since thissometimes provides insight into the cause ofthe distortion. In Mrs. X’s case, the frequencyresponse curve does shed light on the possiblecause of distortion at high input levels. Mrs.X’s behind-the-ear hearing aid had anundamped earhook when she arrived. Thetwo resonant peaks due to sound channellength and receiver characteristics can beseen on the plot in Figure 5, one at 1500 Hzand one at 3000 Hz. Her earhook was replacedwith a 1500 Hz damped earhook.The dashedline on Figure 5 reveals the new frequencyresponse curve. The harmonic distortion testwas rerun with the new earhook, and theresults are depicted in Figure 6.The distortionis now at 10% or lower across frequencies.

These harmonic distortion measures athigh input levels are in agreement with thereported use of output compression limiting.When peak clipping is employed, highdistortion generally is noted at levels intenseenough to drive the instrument intosaturation. The detrimental effects of peakclipping on speech recognition ability andsound quality have been established (Prevesand Newton, 1989; Hawkins and Naidoo,1993). Output compression limiting is theappropriate way to limit the hearing aidsignal, and this is what is employed in Mrs.X’s current hearing aid.

The real-ear aided response measuresreported in Figure 4 were conducted withthe new earhook at user volume controlsettings. Mrs. X may find that she canincrease her volume control position nowthat the distorting peak has been removed.If she does this, she may achieve betteraudibility in the low and midfrequencieswithout discomfort in the high frequencies

since output limiting will restrict the overalloutput. In addition, the undamped peak mayhave made the hearing aid more susceptibleto feedback, which was one of Mrs. X’s originalconcerns.

USING THE TELEPHONE WITH THECURRENT HEARING AID

The electroacoustic analysis is used toevaluate the function of the telecoil

circuitry as well. The Simulated TelephoneSensitivity—Sound Pressure Level forInductive Telephone Simulation (STS-SPLITS) is measured (Figure 7). As can beseen from the graph, the telecoil has a flatfrequency response that is appropriate for thetelephone. The STS-SPLITS value providedindicates the change in volume control thatwould be required to achieve a similarresponse to the microphone setting at themeasured volume control. When the SPLITSwas measured at user volume control setting(approximately a VC setting of 2 with a rangeof 1–4), the measured response was -14 dB.This result indicated that the patient wouldhave to increase the volume control (VC) toobtain the same response on the telephone asshe obtained through her microphone at usegain setting. At full-on VC position, the STS-SPLITS was -4 dB (Figure 7), which indicatedthat even at full-on setting, the telecoilresponse was weaker than the microphoneresponse that one would presume to be thecorrect response for the individual.

Figure 7. The telecoil response plotted as outputacross frequency.

The last portion of the worksheetpresented in Appendix A (unresolved issuesbased on patient interview and observation)is completed during the patient interview.Some of these issues are raised by the patient,and others must be presented as questions tothe patient.

DESCRIBING RESULTS

At this juncture in the evaluation, thepatient’s self-report of communication

difficulty as assessed by the APHAB (thecomplete audiometric evaluation thatprovides insight into degree, configuration,and site of lesion of hearing loss as well asword recognition in quiet) and the currentstatus of the individual’s hearing aid isknown.All results thus far point to the patienthaving significant communication difficultyin a wide variety of communication situations(as evidenced by the APHAB) using hercurrent hearing aid. This is consistent withmoderate-to-severe hearing loss with verypoor word recognition.

At this point, it would be tempting toprovide a recommendation consistent with thephilosophy of the clinic. This would includebinaural instruments staying with thebehind-the-ear style due to the degree ofhearing loss. It is reasonable to recommendthe same signal processing for both ears, andit also would be reasonable to improve thetechnology that the patient is using ratherthan matching her current technology in thesecond hearing aid. The improvement mightconsist of wide dynamic range compressionallowing the patient to differentiate theaudibility for moderate and high input levelsand multiple channels that would allow fine-tuning of the audibility response consideringthe patient’s very poor high-frequencyhearing, transitional midfrequency hearing,and moderate hearing loss in the lowfrequencies. Given the telecoil response ofthe current hearing aids, it would bereasonable to include a programmable telecoilin the new instruments in order to provide anoptimum setting for telephone listening. Anautomatic telecoil (switches automaticallywhen the magnet from the telephone is inclose proximity to the hearing aid) might beconsidered if that would make telephonecommunication easier (no switching needed).The automatic telecoil does not work withassistive listening devices so the need for

these would have to be ruled out or anautomatic telecoil with an optional telecoilswitch would have to be selected.

Considering the results of the BN and RVsubscale of the APHAB and the very poorword-recognition results, directionalmicrophones would be a reasonablerecommendation.There are no data indicatingif degree of hearing loss and degree of word-recognition difficulty interact with ability tobenefit from directional microphonetechnology.There are data to indicate that thelaboratory advantage of directionalmicrophones does not predict the real-worldbenefit of directional microphones (Surr et al,2002). Walden et al (2003) indicate thatdirectional microphones are an environmentalmanipulation and the patient must be taughthow to position themselves and how toidentify appropriate listening situations forbeneficial directional microphone use. Thesignal must be in front of the listener with thenoise behind with a fairly low level ofreverberation in the room so the noise trulyis coming primarily from behind.

FORMALIZED PATIENT INTERVIEW

Rather than proceed with what might beconsidered expected recommendations,

the patient was interviewed in order tocomplete two forms used in the clinic. Inorder to better communicate during thisprocess, the individual’s current hearingaid(s) are worn. If the patient does not havehearing aids, an assistive listening devicemay be used so a comfortable conversationcan be conducted with the patient. If thepatient has hearing aids, he/she inserts thehearing aid(s) so the clinician can see if thepatient is able to do this easily and how thepatient manipulates the hearing aid(s). Anindividual may report daily hearing aid use,but when the patient attempts insertion,he/she does not know which ear the hearingaid goes in or how to put it in the ear. Inother circumstances, the patient may havedifficulty with insertion just because ofmanual dexterity challenges. This was thecase for Mrs. X. It quickly became apparentthat Mrs. X knew how to put her hearing aidin, but her hands were not cooperating. Shehad the greatest difficulty getting the upperportion of the skeleton mold tucked into theconcha. She finally got the hearing aid seatedand was asked if the clinician’s voice was


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comfortable or if she needed to turn thehearing aid volume control up or down. Sheindicated that she always set it in the middleprior to putting the hearing aid in because shecould not feel the wheel or switches (themicrophone/telecoil setting) on the hearingaid. She did indicate that voices were at acomfortable level. Due to these difficulties,Mrs. X was asked how she handles replacingbatteries, and she indicated that the helperthat comes to her home once per weekchanges the battery at that time. The simpleaction of handing Mrs. X the hearing aid toplace in her ear will later influence severaldecisions in the recommendation process.

A SYSTEMATIC APPROACH

The use of the forms described belowshould encourage consistent practice by

multiple clinicians at a primary clinic and/orsatellite locations. The Hearing Demand,Ability, and Need Profile (HDAN; Palmerand Mormer, 1997 [see Figure 8]) provides asystematic interview format and datacollection sheet. This process was

implemented in response to retrofitting/remaking instruments, instrument returns,and the ability to provide complete hearinghealth care to patients. By asking specificquestions about alerting situations,communication situations, and “other”activities (see Figure 8), the clinician canavoid costly remakes and returns as well asprovide more comprehensive hearing healthcare to patients. This sheet delves into all ofthe types of signals to which an individualmay need to respond and helps inform thefinal instrument(s) selection. Often, assistivelistening devices (ALD) are not initiallyconsidered by clinicians; however, if theresults of the various tests and questionnairesdescribed above indicate poor wordrecognition and problems in noise, then theneed to recommend ALDs and hearing aidscompatible with ALDs would become clear.

HEARING DEMANDS AND NEEDS

The HDAN (Figure 8) is created so theclinician can quickly ask about each

situation (left-hand column) in each

Figure 8. Patient results for the Hearing Demand, Ability, and Need Profile. Adapted from Palmer (1992).

environment that applies to the patient(home, work, travel) with the hearing aids onand off (“off” applies to night time or if anonuser is being interviewed). If the cause ofthe difficulty can be identified, it is indicatedin the column under “The Problem is Dueto….” If the patient currently uses technologyor strategies, these are indicated to the farright. Indicating current compensationmethods assists the audiologist in designingsolutions that work well with or even makeuse of current solutions being employed by thepatient. The alerting and personalcommunication categories are self-explanatory. The “Other Activities” sectionis very helpful in finding out needs peculiarto specific patients (e.g., the need to use astethoscope with hearing aids, theparticipation in particular sports or otherhobbies that may require special solutions).

The use of the HDAN was particularlyenlightening with Mrs. X. She does not havedifficulty hearing her telephone ringer,doorbell, or smoke detector with her hearingaid on or off. Mrs. X does not work andindicated that she does not travel except todoctor’s appointments when her daughter orson visit. When asked about hearing sirensor turn signals, Mrs. X indicated that she nolonger drives. Under “PersonalCommunication,” Mrs. X indicated she hasgreat difficulty on the telephone and uses itexclusively to communicate with both of her

adult children, neither of whom live nearher. Further, she indicated that she needs torest on and off all day, and when she is awakeshe likes watching the news. She has alwaysenjoyed keeping current with world events.She indicated she has significant difficultyunderstanding the television with or withouther hearing aid. When asked if she had triedlooking at the captioning, she said it wasvery confusing to try to listen and read, andher preference would be to listen if possible.

When asked about difficulty in one-to-one, group, or large room communication,Mrs. X indicated that she had no difficulty inthese situations because she was never inthem.This, of course, is in direct conflict withthe results of the APHAB that was completedearlier. Upon further discussion, Mrs. X andher daughter indicated that Mrs. X’s mobilityis such that she never leaves her home now.A service does her shopping and cleaningweekly. She communicates with the individualfrom this service in the quiet of her home. Shehas no living friends where she is and onlycommunicates by telephone to her childrenwho live at a great distance (over 500 mileseach). She has no plans of moving nearer toher children; they have no plans to movenearer to her; and she has no plans of enteringany type of retirement or partial carecommunity at this time.

The discussion that was prompted bythe questions on the HDAN made it clear


800

Figure 9. Patient’s current performance and expected performance recorded on the Patient Expectation Work-sheet.


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that Mrs. X was living alone, had very limitedmobility, was no longer socializing, and wasin great need of adequate telephonecommunication for safety and enjoyment,and in need of television listening for herenjoyment. None of this had been apparentfrom the brief history prior to the audiometricevaluation or from the APHAB. Indeed, theAPHAB results were misleading in thisparticular case. Mrs. X took the instructions“If you have not experienced the situation wedescribe, try to think of a situation that youhave been in and respond for that situation”very literally. She was responding as if shewere still doing these things and knew thatshe would have great difficulty in them. Areasonable interpretation of her APHABscores would have been that she had difficultyin a variety of social situations and did notmind loud sounds although in her initial casehistory she reported that loud sounds didnot sound good. In reality, she was never inany of these situations (social or aversive).Interestingly, the two difficult situations thatthe HDAN identified are not situations thatare investigated by the APHAB (telephoneuse and television viewing). Mrs. X wasquestioned further about her reaction to loudsounds, and she indicated that she did not likethe sound quality when there were loudsegments on television. Sound quality hasalready been addressed and most likely wouldresolve this problem.

EXPECTATIONS

Identifying two expectations from thepatient is the next step. The “Patient

Expectation Worksheet” (Figure 9) is usedfor this purpose (Palmer and Mormer, 1997).Although in Mrs. X’s case, only two areas ofneed were identified on the HDAN, manypatients will have multiple issues (hearingvarious alerting devices, telephone listening,television listening, group communication,etc.). The expectation worksheet is used todefine what the patient cares most about interms of improving performance throughwhatever treatment is recommended. Onlytwo expectations are solicited becauseMormer and Palmer (2002) found thatpatients recall no more than two goals overtime reliably. Mrs. X had no difficultyidentifying telephone communication withher adult children and television viewing asprimary goals of whatever solution we would

offer. The “C’s” on the worksheet indicatehow Mrs. X feels she currently is functioning,and the “E’s” illustrate how she expects tofunction after intervention. The audiologistmay want to provide a check mark wherethe patient will most likely function given thetreatment that is chosen.This can help createrealistic expectations for the patient.

In Mrs. X’s case, she should be able tocommunicate well on the telephone most ofthe time and understand the television mostof the time (as opposed to almost always).Theexpectation worksheet provides a posttestmeasure after intervention for which thepatient is asked to mark how he or she isfunctioning now. This also is a good reminderto the patient of what was expected from theamplification. It is very rewarding for apatient to find that his/her expectations havebeen met or exceeded. It also helps keep thepatient focused on realistic goals.

RECOMMENDATIONS

The initial audiometric results, APHAB,and case history had the audiologist

considering recommending binauralamplification. The findings from the HDANand “Expectations Worksheet,” however,forced the audiologist to consider otherrecommendations. Mrs. X communicates inthe quiet of her own home with one helper,with her children on the telephone, andpotentially with emergency personnel on thetelephone, and she listens to the television inorder to stay informed about current events.With her helper, her current hearing aid issufficient. It provides audibility for soft,moderate, and loud sounds across frequencieswhere she has enough hearing to benefitfrom an amplified signal. Her complaints ofdistortion and feedback have been resolvedby simply adding a damped earhook. It isunlikely that the addition of a second hearingaid will add significant benefit to this specificcommunication situation.

THE TELEPHONE SOLUTION

As for the telephone, Mrs. X’s currenttelecoil has a reasonable response (4 dB

lower than the microphone response) whenthe volume control is set to full on. However,Mrs. X has indicated that she cannotmanipulate the volume control due todexterity problems, so this is not helpful. A

new hearing aid with a programmable telecoilcould provide a stronger response withoutmanipulating the volume control. Thisassumes that Mrs. X can manipulate thetelecoil switch without having to remove herhearing aid to see where the switch is. Itbecame clear in the patient interview thatMrs. X does not have the dexterity to use thetelecoil switch well. Another option would beto replace her current hearing aid with ahearing aid with an automatic telecoil. Athird option would be to provide Mrs. X withan amplified stand-alone telephone. Thedecision regarding telephone use wasimpacted by a solution to listening to thetelevision. The intertwining need forcommunication on the telephone and listeningto the television had an impact on the finalrecommendation. This is described in thenext section.

THE TELEVISION SOLUTION

Mrs. X has indicated that televisionviewing is her primary enjoyment in

life and her way of keeping in touch withworld events. It is evident that Mrs. X is welleducated and well informed and would liketo continue this activity. She revealedsignificant frustration at no longer being ableto understand what was being said ontelevision. She describes becoming exhaustedand exasperated while trying to listen totelevision with her current hearing aid.Considering Mrs. X’s hearing ability and herdesire to sit across the room from thetelevision, it is unlikely that binauralamplification of any type will greatly enhanceMrs. X’s television listening ability.

An ALD (infrared or frequency modulated[FM]) that places the transmittingmicrophone directly at the televisionloudspeaker and sends the amplified signaldirectly to Mrs. X’s hearing aid (via telecoilor direct audio input) or ear (use of externalreceiver) will likely provide the greatestbenefit. To receive a signal with high signal-to-noise ratio, Mrs. X would need to eitherwear the earphones that go with these devicesor purchase new hearing aids with directaudio input or programmable telecoils witha switch. Again, the manual dexteritydifficulty in either plugging in a direct audioinput or switching to telecoil is encountered.For these reasons, it was decided that Mrs.X would use an assistive listening devicewith a headset (independent from hearing

aids) with the television. An infrared devicewas chosen because Mrs. X is always in lineof sight of the television, and the cost isreduced compared to an FM system. Therealso is less chance of interference from othernearby signals. If she were more mobile whilewatching television, an FM system would bea better choice.

Since Mrs. X will not be wearing herhearing aid while watching television (whichshe does during the majority of her day), itwas decided to provide a stand-aloneamplified telephone. The patient would notwant to have to remove the television headsetand insert her hearing aid(s) with automatictelecoils in order to answer the telephone.Thiswould create an unmanageable situation.Now the only complication was that when thehelper comes to the house once per week,Mrs. X would need to put in her hearing aid.She indicated that she was comfortable withswitching from the television device to herhearing aid and she could continue to use theamplified telephone on the unaided earduring these times. To improve Mrs. X’scomfort in inserting her hearing aid, a canalearmold was made to replace the skeletonearmold. This fit eliminates the need to tuckany part of the earmold into the concha andallows for an easier insertion. The other one-to-one communication Mrs. X engages in iswhen her children come to visit.This is in thequiet of her house, but she indicated thatshe enjoys speaking with them while theywatch television programs. For this purpose,the headset that was ordered for the televisiondevice was equipped with an environmentalmicrophone that can be turned up or down.This allows the television device to functionas a hearing aid for listening to individualsnearby.

UNRESOLVED ISSUES

At this point, the section of the worksheettitled “Unresolved issues based on

patient interview and observation” (seeAppendix A) was reviewed, and it was foundthat difficulty in noise, difficulty in localizingsounds, and difficulty understanding whensounds originate from one particular sideare not of consequence to Mrs. X because ofher lifestyle. Feedback had been a problem butwas resolved when the 1500 Hz peak wasreduced. Mrs. X also may have beenexperiencing feedback because of insertionproblems with her earmold.This was resolved


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by supplying a new, canal-style earmold. Mrs.X does not have a problem with the soundquality of her own voice.

Mrs. X’s disappointment in sound qualityof outside signals was resolved throughdamping the earhook of her hearing aid andby providing excellent sound quality devicesspecifically for the telephone and television.Mrs. X had difficulty communicating on thetelephone and understanding the television(under “Other” in Appendix A), and thesesituations were resolved with specific devices.

Most clinicians appreciate the ability ofwide dynamic range compression signalprocessing to produce audible sound at soft,moderate, and loud input levels in anautomatic fashion. Data suggest that thistype of signal processing works as well orbetter than linear signal processing (Jenstadet al, 1999; Jenstad et al, 2000; Marriage andMoore, 2003), which eliminates the concernthat the compression itself might distort thesignal in a detrimental way. Conversely, alinear response is designed to provideappropriate gain for moderate input levelswhile soft sounds generally are too soft andloud sounds are too loud withoutmanipulation of the volume control.

In the case of more severe hearing lossessuch as Mrs. X, the fact remains that well-fitlinear and WDRC hearing aids perform in asimilar manner. Because of the high amountof gain needed to make soft and moderatesounds audible, the linear hearing aid isoperating in compression (output limitingcompression) most the time anyway. A widedynamic range compression instrumentmight be able to employ slightly lesscompression for soft inputs, but it too wouldbe at fairly high compression ratios formoderate and loud input levels in order tokeep the signal within the severely reduceddynamic range. For this reason and all of theother specific patient needs described above,new hearing aids were not pursued for thispatient. In Mrs. X’s well-definedcommunication situations, there is no reasonto believe that binaural amplification willbe of significant benefit, so a second hearingaid with similar signal processing was notpursued.

Mrs. X left the clinic with a new telephoneamplifier with large print and large buttonsalong with a volume control wheel. She alsoleft with an infrared device. It was ideal tohave these items in stock so Mrs. X’s daughter

could install them for her when they returnedhome.

FOLLOW-UP VISIT

Mrs. X received her new earmold twoweeks after her initial visit and

immediately inserted it with ease. Becausethe trip to the clinic is a hardship for Mrs. Xand her children, the postassessmentmeasures were collected at this time ratherthan scheduling another visit. Normally, asecond version of the APHAB is provided,and the change revealed by the benefit scoresis examined.Although this can inform furthertreatment or counseling needed by thepatient, this is largely used for quality controldata. In Mrs. X’s case, no change was expectedin her responses because she would still bethinking back to how she used to do in all ofthese activities. For this reason, the APHABwas deemed an inappropriate posttreatmentmeasure for this patient.

Mrs. X did complete the postassessmenton the “Patient Expectation Worksheet”(Figure 9). She indicated that she now heardwell on the telephone almost always andunderstood television most of the time. Afinal result within one category of thepatient’s expectation is considered a goodoutcome. In addition, Mrs. X indicated thatshe enjoyed the television solution becauseshe naps periodically throughout the dayand it is simple to remove the headset, nap,and then replace the headset when she is upagain. Previously, she had found it veryfrustrating to go through the process ofremoving and replacing her hearing aid.

The rechargeable battery needed in theinfrared system was large enough that Mrs.X did not have difficulty inserting it for useor inserting it into the recharging space. Anadded benefit to this particular set of solutionsfor a patient with extremely limited mobilityand an inability to make the trip to the clinicis that the devices are sturdy and rarely needrepair compared with traditional hearingaids. If repair is needed, it could be done bymail with the assistance of her weekly helper.There is no need to see the patient if a stand-alone television or telephone device is notworking. In addition, if Mrs. X’s hearing lossworsens, she can compensate by turning upthe volume control on her telephone andtelevision device. She would not need to comeinto the clinic for any type of “retuning.” A


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patient’s access to the clinic has to be oneconsideration in formulating a solution.

With the assistance of an organizedmethod to examine Mrs. X’s specific listeningand communication needs in the context ofher particular lifestyle, a set of appropriateand cost-effective solutions were offered.Rather than starting with a new hearing aidor binaural hearing aids, Mrs. X’s specificlistening needs were addressed.This includedsolutions for the telephone, television, andoccasional one-to-one visiting. The protocolsuggested in this report allowed Mrs. X’shearing demands, needs, and expectationsto be viewed prior to makingrecommendations. Mrs. X is comfortable withthese solutions, and she and her familyperceive significant benefit. The clinic hasdocumentation of the success of this processthrough the postexpectations worksheet.

REFERENCES

American National Standards Institute. (1996)American National Standard Specification of HearingAid Characteristics (ANSI S3.22). New York:Acoustical Society of America.

Baer T, Moore BCJ, Kluk K. (2002) Effects of low passfiltering on the intelligibility of speech in noise forpeople with and without dead regions at high fre-quencies. J Acoust Soc Am 112(3):1133–1144.

Berger K, Hagberg E. (1982) Gain usage based onhearing aid experience and subject age. Ear Hear3:235–237.

Byrne D, Dillon H, Ching P, Katsch R, Keidser G.(2001) The NAL-NL1 procedure for fitting nonlinearhearing aids: characteristics and comparisons withother procedures. J Am Acad Audiol 12:37–51.

Byrne D, Dirks D. (1986) Effects of acclimatizationand deprivation on non-speech auditory abilities. EarHear 12(3):29S–37S.

Cord M, Surr R, Walden B, Olson L. (2002)Performance of directional microphone hearing aidsin everyday life. J Am Acad Audiol 13:295–307.

Cornelisse L, Seewald R, Jamieson D. (1995) Theinput/output formula: a theoretical approach to thefitting of personal amplification devices. J Acoust SocAm 97(3):1854–1864.

Cox R. (2004) Memorandum: administration of theContour Test.

Cox R, Alexander G. (1995) The abbreviated profileof hearing aid benefit. Ear Hear 16:176–183.

Dirks D, Kincaid G. (1987) Basic acoustic considera-tions of earcanal probe measurements. Ear Hear8(Suppl. 5):60S–67S.

Etymotic Research. (2001) The SIN Test. CD-ROM.Elk Grove Village, IL: Etymotic Research.

Hawkins D. (1987) Variability in clinical earcanalprobe microphone measurements. Hear Instrum38(1):30–32.

Hawkins D, Mueller HG. (1986) Some variables affect-ing the accuracy of probe-tube microphone measuresof hearing aid gain. Hear Instrum 37(1):8–49.

Hawkins D, Naidoo S. (1993) Comparison of soundquality with asymmetrical peak clipping and outputlimiting compression. Am J Audiol 4:221–228.

Jenstad L, Pumford J, Seewald R, Cornelisse L. (2000)Comparison of linear gain and WDRC hearing aidcircuits II: aided loudness measures. Ear Hear21:32–44.

Jenstad L, Seewald R, Cornelisse L, Shantaz J. (1999)Comparison of linear gain and WDRC hearing aidcircuits: aided speech perception measures. Ear Hear20:117–126.

Killion M, Revit L. (1987) Insertion gain repeatabil-ity versus loudspeaker location: you want me to putmy speaker W-H-E-R-E? Ear Hear 8(Suppl.5):68S–73S.

Kochkin S. (2003) MarkeTrak VI: on the issue of value:hearing aid benefit, price, satisfaction, and repur-chase rates. Hear Rev 10(2):12–18, 22–26.

Leijon A, Lindkvist A, Anders R, Israelsson B. (1990)Preferred hearing aid gain in everyday use after pre-scriptive fitting. Ear Hear 11:299–303.

Lindley G. (2001) Audiologist- versus patient-drivenhearing aid fitting protocols. Semin Hear22(2):139–161.

Marriage J, Moore BCJ. (2003) New speech tests revealbenefit of wide-dynamic range, fast-acting compres-sion for consonant discrimination in children withmoderate to profound hearing loss. Int J Audiol42:418–425.

Mormer E, Palmer CV. (2002) Reliability of hearingaid expectation responses. Paper presented at theannual meeting of the American Academy ofAudiology, San Antonio, TX.

Mueller HG, Powers T. (2001) Consideration of audi-tory acclimatization in the prescriptive fitting ofhearing aids. Semin Hear 22(2):103–124.

Nielsen D, Nielsen J, Parving R. (1990) Harmonic dis-tortion measurements in clinical hearing aid fitting.Scand Audiol 19:55–58.

Palmer C. (1992) Assistive devices in the audiologypractice. Am J Audiol 2:37–57.

Palmer C. (2003) A checklist/protocol for audiologists:is this hearing aid appropriate for this individual? JEduc Audiol 11:49–68.

Palmer CV, Mormer E. (1997) A systematic programfor hearing aid orientation and adjustment. Hear Rev1:45–52.

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hearing aid gain. In: Jensen JH, ed. Hearing AidFitting: Theoretical and Practical Views. Proceedingsof the 13th Danavox Symposium, Copenhagen.Copenhagen: Danavox, Inc., 129–152.

Preves D, Newton J. (1989) The headroom problemand hearing aid performance. Hear J 42:19–26.

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Scollie S, Seewald R. (2002) Evaluation of electroa-coustic test signals I: comparison with amplifiedspeech. Ear Hear 23(5):477–487.

Scollie S, Seewald R, Cornelisse L, Jenstad L. (1998)Validity and repeatability of level-independent HLto SPL transforms. Ear Hear 19(5):407–413.

Sousa P. (2002) Relationship between audibility andreal-world hearing aid benefit and satisfaction. JRehabil Res Dev 39(5):112–124.

Stelmachowicz P, Dalzell S, Peteson D, Kopun J, LewisD, Hoover B. (1998) Comparison of threshold-basedfitting strategies for nonlinear hearing aids. Ear Hear19:131–138.

Stelmachowicz P, Hoover B, Lewis D, Kortekaas R,Pittman A. (2000) The relation between stimulus con-text, speech audibility, and perception fornormal-hearing and hearing-impaired children. JSpeech Hear Disord 43:902–914.

Stelmachowicz P, Kopun J, Mace A, Lewis D. (1996)Measures of hearing aid gain for real speech. EarHear 17(6):520–527.

Stelmachowicz P, Pittman A, Hoover B, Lewis D. (2002)Aided perception of /s/ and /z/ by hearing-impairedchildren. Ear Hear 23:316–324.

Surr R, Walden B, Cord M, Olson L. (2002) Influenceof environmental factors on hearing aid microphonepreference. J Am Acad Audiol 13:208–322.

Tecca J,Woodford C, Kee D. (1987) Variability of inser-tion-gain measurements. Hear J 2:18–20.

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Turner C, Cummings K. (1999) Speech audibility forlisteners with high frequency hearing loss. Am JAudiol 8:47–56.

Walden B, Schuchman G, Sedge R. (1977) The relia-bility and validity of the comfort level method ofsetting hearing aid gain. J Speech Hear Disord42:455–461.

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Appendix A. Evaluation of Current Hearing Aids

Name: ____Mrs. X_____________________________ Date:____10/10/04______________

Right Hearing Aid: Left Hearing Aid:

Company Oticon _________________ _______________________________

Model Personic 425____________ _______________________________

Serial # _XXXXXXXX__________ _______________________________

Circle Style: BTE ITE ITC CIC BTE ITE ITC CIC

Sound is audible for quiet inputs

R L

_x_ __ Yes

__ __ No:

R L

__ __ modification to current hearing aid response

__ __ new hearing aid circuitry would be required to achieve this goal

__ __ new hearing aid style would be required to achieve this goal

__ __ new earmold would be required to achieve this goal

__ __ patient must attempt new wearing habits to achieve this goal

__ __ degree of hearing loss precludes audibility to soft sounds in some frequencies

Sound is audible for moderate inputs

R L

x__ __ Yes

__ __ No:

R L






__ __ degree of hearing loss precludes audibility to moderate sounds in some frequencies

Sound is audible for loud inputs

R L

x__ __ Yes

__ __ No:

R L






__ __ degree of hearing loss precludes audibility to loud sounds in some frequencies

Loud sound is at or just below uncomfortable loudness level

R L

x__ __ Yes (yes for higher frequencies)

x__ __ No: (no for lower frequencies)

R L


_x_ __ new hearing aid circuitry would be required to achieve this goal





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Bandwidth is adequate for communication, patient’s environment, and any special requirements

R L

_x_ __ Yes

__ __ No:

R L




__ __ degree of hearing loss precludes audibility across some of the frequency range

Good sound quality while the hearing aid is providing audible sound across input levels

R L

__ __ Yes

x__ __ No:

R L


_x_ __ modification to current hearing aid response

Unresolved issues based on patient interview and observation:

______ Difficulty in noise

___ binaural hearing aid use

___ modification of hearing aid response

___ patient must attempt new wearing habits to achieve this goal

___ different circuitry/signal processing recommended (e.g., directional

microphones and/or assistive listening devices)

______ Difficulty localizing sounds



___ modification of current hearing aid response

___ new hearing aids required

______ Difficulty when sound originates from one particular side


___ routing of signal to opposite ear (e.g., CROS, BICROS, transcranial

CROS, BAHA)


___ modification of current hearing aid response

_x_____ Feedback

_x__ modification of earmold or shell

_x__ modification of hearing aid response

___ different circuitry/signal processing recommended

(e.g., feedback cancellation)

______ Disappointment in sound of own voice

___ modification of hearing aid response

___ modification of earmold/shell (lengthen canal portion)

___ modification of vent (open venting if possible)


__x____ Disappointment in sound quality

_x__ modification of hearing aid response


__x____ Difficulty communicating on the telephone

___ reinstruction

___ modification of telecoil response

___ addition of telecoil circuitry

_x__ other phone solution


_______ Difficulty coupling to ALDs

___ reinstruction

___ change hearing aid style

___ modification to current hearing aid (e.g., add t-coil or DAI, enable

DAI, etc.)

___ equipment addition (e.g., neckloop, DAI cord, etc.)

__x_____ Other (describe problem and solution below)

OVERALL RECOMMENDATIONS:


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quantifying and responding to patient needs and expectations · embargo, no es un audiograma móvil...

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