Efficacy of Digital Hearing Aids

1
Dr. Ruth Bentler
Associate Professor of Audiology
Ph.D 1987, Univ. of Iowa
Hearing aid technology with emphasis in
evaluation of device effectivness and user
satisfaction
2
Dr. Ruth Bentler
Associate Professor of Audiology
3
Where is Iowa?
4
Clinical Evaluation of Hearing systems
Dr. Ruth Bentler
5
U.S. Clinical Trials

• Ruth Bentler, Ph.D.
• The University of Iowa

6
Food Drug Administration (FDA)

• False advertising must cease, or product removed
  from market
• Any advertised claims must be supported by
  clinical trial data (with certain restrictions
  on design)
• Controls eased.

7
I. Clinical trials (Bentler, Fabry Jerger)

• Comparison to well-fit linear hearing aid
• Difference in outcome measures is small and for
  the most part can be attributed to gain
  differences and output limitation type (limiter
  versus peak clipper).

8
Quality Judgment 60 dB (10 S/N)
9
Quality Judgment 75 dB (5 S/N)
10
Speech in Noise 75 dB (5 S/N)
11
Effort 75 dB (5 S/N)
12
II. Clinical trials (Valente Fabry)

• Comparison to what the subject came in the door
  with
• Newer technology showed improved performance both
  objectively and subjectively
• Goodness of fit unclear for subjects previous
  hearing aids.

13
Mean LP Score (SPIN), Site 1
14
Mean LP Score (SPIN), Site 2
15
Mean HINT (S/N), Site 1
16
Mean HINT (S/N), Site 2
17
III. Clinical trials (Bentler Humes)

• Comparison to the unaided condition
• Comparison across directional and omnidirectional
  modes
• Subjective results compared to the norms of
  successful hearing aid users
• Wise design.

18
Mean NST Scores
19
Mean HINT Scores
20
Mean HHIE Scores
21
IV. In-House Reports

• In lieu of multi-site independent labs
• Beta sites obtain data relative to improvement of
  listening (via speech perception tasks or
  self-report inventories)
• Goodness of fit and bias of high tech unclear

22
Hearing in Noise (Mean ratings)
23
Hearing in Quiet (Mean ratings)
24
V. Assessment of fit/features

• Bernafon SMILE
• Two sites Mayo Clinic U of Iowa
• Two rrimary questions posed
• Is NAL-NL1 (as configured by Noah)adequate or is
  fine tuning required?
• Does the Bernafon algorithm for listening in
  noise provide easier listening without
  compromising speech intelligibility?

25
Methodology

• 25 subjects from each site
• One-half were new users (less than 60 days)
• One half experienced users (at least 6 months)
• All were fit with half-shell ITE styles
• One-third unilaterally
• Two-thirds bilaterally

26
(No Transcript)
27
(No Transcript)
28
(No Transcript)
29
Which condition did you prefer?
30
How much remote vs VCW?

• 20/24 subjects used remote 100 of time
• 2/24 subjects used remote 90-95 of time
• 1/24 subject used remote 50 of time
• 1/24 subject never adjusted the volume

31
How much are you willing to pay?
32
How much Program 1 vs Program 2?(Did not ask
first 9 subjects)

• 100 of time Program 1 (1)
• 90-98 of time Program 1 (9)
• 70-80 of time Program 1 (2)
• 40-50 of time Program 1 (2)
• 0 of time Program 1 (1)

33
What factors are most important?

• Speech Clarity/Understanding (16)
• Cost (4)
• Size/Style (3)
• Reliability (2)
• Technology (1)

34
In what situations did you receive the most
benefit?

• Small group situations (18)
• TV (6)
• Meetings (5)
• Church (4)
• Telephone (2)
• Listening to music (1)

35
In what situations did you receive the least
benefit?

• Large Groups (13)
• Car (4)
• Church (2)
• No times (2)
• Plays (1)
• Work Site (DOT)(1)
• Telephone (1)

36
How do these HAs compare to your first/most
recent HAs?

• Head shoulders better
• No Comparison (2)
• First One Yuck
• Night Day
• Like a Model T compared to modern car
• Better (2)
• Much better (3)

37
Conclusions

• The subjects, in general, preferred the NAL-NL-1
  response
• The NAL-NL-1 gain approximated by the OASIS
  software was not significantly different than
  that measured following adjustment with real ear
  measures

38
Conclusions, cont.

• Program 2, intended for higher noise
  environments, did not result in speech perception
  ability
• Subjects used the remote control almost
  exclusively over the VCW

39
Conclusions, cont.

• 5. Bernafon provided outstanding support for this
  project (Donna Haider, Bob Traynor, and all those
  behind the scenes in Minnesota and Switzerland)