Conversations on Verification Part I. Hearing Aid Fitting Errors in Oregon Ron Leavitt, Nikki Clark & Camille Jenkins

Transcription

1 Conversations on Verification Part I Hearing Aid Fitting Errors in Oregon Ron Leavitt, Nikki Clark & Camille Jenkins

2 DISCLOSURE STATEMENTS RON LEAVITT, AUD Financial Disclosures: Nothing to disclose Non-Financial Disclosures: Nothing to disclose

3 About our group... in the beginning... Oregonian October 1985 October 2015

4 So now we know everyone let s get to the presentation

5 What peaked our interest in this topic?

6 Consumer Reports followed 12 patients for 6 months as they shopped for and used hearing aids.

7 Two-thirds of the 48 aids they bought were misfit: they amplified too little or too much.

8 CR reports The most consequential decision is finding the proper professional from whom to buy..

9 This is not a project for the faint-hearted because the industry is anything but standardized.

10 Shoppers encountered a variety of providers, including hospital-based clinics and strip-mall storefronts, all legally able to fit a hearing aid, but with varied resources and expertise.

11 This study was criticized as being lacking scientific detail.

12 So we decided to do a larger study with more scientific detail

13 To see if hearing aid programming had gotten any better.

14 Let s start with the method we used: n=97 adults who came to our clinic from 24 other facilities throughout Oregon.

15 The average subject age was 75 years with a range of 23-93

16 In total 174 hearing aids were worn by the 97 subjects.

17 Fourteen different hearing aid brands were represented.

18 Hearing aids were programmed by 14 audiologists (representing 114 hearing aids) and 9 hearing aid dispensers (representing 56 hearing aids).

19 This was the subjects average hearing loss with range markers.

20 The average age of the hearing aids was 3.5 years with a range of 3 months to 8 years.

21 The subjects were walk-in patients from other facilities who contacted our clinic for hearing evaluation, hearing aid evaluation, tinnitus evaluation therapy, auditory processing disorder complaints or hearing aid repair issues. Several were physician referrals.

22 9 facilities were staffed exclusively by hearing instruments specialists while 14 others were in medical centers, otolaryngology clinics and private audiology practices, staffed by audiologists.

23 All 97 of our subjects ear canals were examined prior to receiving a comprehensive hearing and hearing aid evaluation and were cleared prior to testing as needed.

24 All hearing aids were analyzed for oxidation and debris using a Med Rx video otoscope. If any such hearing aid problems were noted the hearing aids were repaired or cleaned prior to evaluation.

25 The audio evaluation consisted of 1. Case Hx 2. Pure-tone air and bone conduction 3.Word recognition in q & noise (MD CNC and Q-Sin respectively. 4. Olsen Noffsinger tone decay 5. Immittance with ipsilateral,contralateral reflexes and reflex decay 6. Pure tone UCLs Hz 7. APD Battery and Stroop Mix/Trail PRN

26 Real ear aided measures were performed with an Audioscan Axiom after each comprehensive hearing test to determine if the subject s hearing aid conformed to an NAL NL-2 target at 50, 65, and 75 db SPL inputs.

27 The root-mean-square deviation from an NAL NL-2 target was calculated for each subject s right and left ears separately at 500, 1000, 2000, 3000 and 4000 Hz for the long-term average speech spectrum at 65 db SPL input using the carrot passage.

28 Why did we choose 500, 1000, 2000, 3000 and 4000 Hz?

29 Let s see what speech sounds our average hearing loss made inaudible

30 Data analysis: Repeated linear, mixed-model measure analysis of variance performed: Frequency error and ear were within subject factors Provider, brand and age were between subject factors

31 Results: The RMS difference between NAL target and measured output at 65 db SPL was significant at every frequency in both right and left ears.

32 Results: Of the 174 hearing aids evaluated 97.7% had an RMS deviation of +5 db or more.

33 Results: and 70% had an RMS deviation of +10 db or more.

34 Here are the hearing aid programming errors for all subjects at each of five frequencies for both ears. Negative values indicate the hearing aid was under fit.

35 Positive values indicate hearing aid was over fit.

36 So on average the hearing aids were too weak at every frequency important for hearing and understanding speech.

37 Specifically at 500 the hearing aids were on average 7-9 db too weak.

38 At 1000 the hearing aids were on average 10 db too weak.

39 At 2000 the hearing aids were on average 8-9 db too weak.

40 At 3000 the hearing aids were on average 13 db too weak.

41 At 4000 the hearing aids were on average 17 db too weak.

42 Using the 5 db RMS criteria established by McCreery, Bentler and Roush (2013) 97.7% of fittings were in error.

43 These data suggest previous self-report surveys from audiologists and hearing aid dispensers regarding use of real-ear measures are greatly inflated.

44 Specifically Mueller and Picou (2010) report 40% routine use of real-ear measures. Mueller, H.G. & Picou, E.M. (2010) Survey examines popularity of real-ear probe-microphone measures. Hearing Journal, 63(5),

45 Leavitt, Clark and Rector (2015) reported 30% of Doctors of Audiology self-report routine use of real-ear measures. Leavitt RJ, Clark AN & Rector CE. (2014) Survey of Selected Audiometric Practices at Academy of Doctors of Audiology Conference Proceedings of Audiology Now, Orlando Florida.

46 Our data resembles that reported by Sanders et al (2015) for five manufacturer s NAL NL-2 target program. Our average error data Sanders J, Stoody T, Weber J, Mueller HG. Manufacturers NAL-NL2 Fittings Fail Real-ear Verification. Hearing Review. 2015;21(3):24.

47 ..suggesting that manufacturer s default programs may have been employed in some of these fittings. Our average error data Sanders et al (2015).

48 ..rather than real-ear verified programming. Our average error data Sanders et al (2015).

49 If there were no data suggesting these fitting errors resulted in unfavorable outcomes for people with hearing loss this recurring % error rate would be inconsequential

50 However, Kochkin et al (2012a) showed lack of hearing aid validation by real ear measures was the number one factor resulting in decreased hearing aid user satisfaction. Kochkin S. MarkeTrak VIII: The key influencing factors in hearing aid purchase intent. Hearing Review. 2012a; 19(3):12-25.

51 Kochkin (2012b) also showed the ability to perceive soft sounds with the hearing aid was the greatest need expressed by hearing aid nonusers which has been repeatedly shown to be related to real-ear verification of aided speech audibility Kochkin S. (2012b). Hearing loss treatment. Better Hearing Institute.

52 Humes (2014) showed that for 98 elderly subjects with hearing loss there were no differences in auditory performance between those subjects and young controls with normal hearing on most auditory tests as long as the hearing loss was corrected such that aided SII approached Humes, L (2014). Understanding the Speech-Understanding Problems of Older Adults. Proceedings of the Acad of Doctors of Audiology Conference, Las Vegas, NV

53 Leavitt and Flexer (2012) showed that reliance upon manufacturer s best fit software and associated under fitting of the subjects hearing aids resulted in decreased speech recognition in noise. Leavitt R., & Flexer, C. (2012). The importance of audibility in successful amplification of hearing loss. Hear Rev, 19(13), 20-23

54 Stiles et al (2012) showed children with mild to moderately severe hearing loss with real-ear verified aided Speech audibility less than 65% demonstrated greater delays in vocabulary development than children with hearing loss with better aided audibility. Stiles DJ, Bentler RA & McGregor KK (2012) The Speech Intelligibility Index and the Pure-Tone Average as Predictors of Lexical Ability in Children Fit with Hearing Aids. J. Speech Hear Res 55(3):

55 McCreery, Bentler and Roush (2013) showed that 55 percent of their 199 subjects showed deviations of five db or more from real-ear verified targets resulting in significant academic difficulties. McCreery, R. W., Bentler, R. A., & Roush, P. A. (2013). Characteristics of hearing aid fittings in infants and young children. Ear and Hearing, 34(6),

56 In a more recent publication McCreery et al (2015) showed that hearing aid wearing schedule and quality of programming significantly affected a number of academic skills in school aged children with hearing loss. McCreery RW, Walker EA, Spratford, M, Bentler, R, Holte, L; Roush, P; Oleson, J; Van Buren, J; Moeller, MP (2015). Longitudinal Predictors of Aided Speech Audibility in Infants and Children. Ear & Hear (36):

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59 Boothroyd and Mackersie (2016) showed that for their 20 subjects who self-programmed their hearing loss for optimum sentence recognition all but one was within + 5 db of an NAL NL-2 target. Boothroyd A & Mackersie C (2015). Self-adjustment of amplification: Efficacy and Candidacy. Paper presented at the Hearing Across the Lifespan Conference Cernobbio,Italy.

60 Thus hearing aid under fitting results in decreased hearing aid user satisfaction (Kochkin, 2012a), decreased word recognition in noise and quiet (Leavitt and Flexer, 2012; Boothroyd and Mackersie, 2016), decreased performance on numerous auditory tests (Humes, 2104) and poorer academic performance for children with hearing loss (Stiles et al, 2012; McCreery, Bentler and Roush, 2014).

61 If one believes that today s deluxe hearing aid features obviate the need for real ear validated aided speech audibility the data of Cox et al (2014) suggests otherwise.

62 Cox and colleagues (2014) questioned whether premium hearing aid features really gave better speech understanding in noise than basic hearing aids with no deluxe features.

63 Hearing aid manufacturers have said this is so for over 25 years

64 This research was published in The Journal of Gerontology Cox, RM, Johnson, JA and Xu, J. (2014). Impact of Advanced Hearing Aid technology on Speech Understanding for Older Listeners with Mild to Moderate Adult-Onset Sensorineural Hearing Loss. Gerontology; 60: Cox, RM, Johnson, JA and Xu, J. (2015). Effectiveness of basic and premium hearing aids on speech understanding and listening effort outcomes.

65 She used 45 blinded subjects. This was their average hearing loss

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67 All 45 subjects wore each pair of premium and basic hearing aids from 2 different manufacturers for one month without knowing which were premium.

68 All hearing aids were programmed to a full NAL NL-2 correction confirmed with realear aided testing

69 At the end of four months all subjects completed standardized questionnaires and open-ended diary items

70 and performed clinical speech understanding tests with all four sets of hearing aids

71 Here s what she and her colleagues found

72 Question 1: Was premium better than basic in the lab?

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75 Question 2: Could these 45 blinded subjects tell any difference between premium and basic in their daily lives?

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80 Remember patient-centered rehabilitation? It is not this

81 But this Real-ear measures and hearing aid use training..

82 In our study 97.7% of these subjects showed deviations from an NAL NL-2 in excess of five db in at least three of five frequencies in both ears well in excess of the nearly 2/3 of hearing aid fitting errors reported by Consumer Reports in 2009.

83 To the extent that under fitting of wellestablished real ear targets results in decreased user satisfaction, decreased word recognition in quiet and in the presence of background noise, decreased performance on numerous auditory tests and reduced academic performance for children wearing hearing aids such errors cannot be tolerated.

84 What else did we learn?

85 There was a significant frequency effect in that the fitting errors were least at 500 and 2000 Hz

86 There was a significant difference in fitting accuracy among brands. Although errors were pervasive among all brands four subsidiary brands and one of the Big Six manufacturers were fit significantly worse than the others.

87 There was no significant ear effect. In other words the errors on the right ear were not significantly different than the errors on the left.

88 There was no significant age of hearing aid effect. In other words the errors were as great on new hearing aids as on old hearing aids.

89 Not surprisingly the difference between NAL NL-2 target vs measured output was significant.

90 Unfortunately, while the audiologist fittings were better than the dispenser fittings the difference did not achieve significance. That would require 231 subjects according to the power analysis.

91 For these 97 patients owning one of the four subsidiary brands increased the likelihood of a bad hearing aid program.

92 The age of hearing aid and ear(s) fit did not change the likelihood of a bad hearing aid program.

93 While audiologists made lesser programming errors on average, the difference was not significant.

94 The likelihood of a hearing aid program with an RMS error of 5 db or greater in these 24 facilities was 97.7 to 1.

95 You might ask with all the outcome data and professional associations supporting real-ear measures why aren t more audiologists achieving an wellresearched target? L

96 We tried to make it easy and won an international award for our attempt.

97 This is the form

98 So why don t audiologists use it and real ear?

99