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Effectiveness of Cochlear Implants in Adults with Sensorineural Hearing Loss Project ID: AUDT0501

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Effectiveness of Cochlear Implants in Adults with Sensorineural Hearing Loss Project ID: AUDT0501 Project Name: Effectiveness of Cochlear Implants in Adults with Sensorineural Hearing Loss Project ID: AUDT0501 Table 1: Invited Peer Reviewer Comments Reviewer1 Section2 Reviewer Comments Author Response3 Advanced Bionics refers specifically to HINT scores, Page ES-3, KQ1: Is it true that all CI indications specify the use while Cochlear Americas 1 Executive Summary of the HINT sentences specifically or do they simply refer to only refers to open-set open-set sentence perception? perception. The final document has been changed to reflect this. Introduction/ Background In the first paragraph there is reference to “two types of hearing loss” – conductive and sensorineural. However, it is important to We have made changes to 1 Page 1, Background acknowledge central hearing loss, particularly when considering reflect this edit. an aging population who may acquire central auditory deficits secondary to strokes. Sensorineural hearing loss is not best characterized by just an attenuation of the highest frequencies of sound. First, any frequency can be attenuated. Second, the attenuation is not necessarily the factor that causes the significant speech Page 1, Background 1st We have made changes to perception difficulties. For a pure attenuation loss acoustic 1 Line, 2nd paragraph reflect this edit. amplification is an excellent options. With increased levels of sensorineural hearing loss, there also comes loss of frequency selectivity and other forms of distortion within the inner ear. These effects cannot be addressed with hearing aids. We have made changes to Page 1, last line of Consider adding “or central” before “deafness.” 1 reflect this edit. background 1 Page 1, Cochlear I find the word “arrange” to be quite unspecific. Aside from a We have made changes to implantation, 2nd to last more complete description of sound processing, even reflect this edit. line on page replacement of the word with something like “analyzes and codes” would be more instructive. Page 2, FDA labeled use, We have made changes to “users” should be possessive. 1 line 1 reflect this edit. We have put the words The word insufficient seems to be incorrectly used here. If Page 2, FDA labeled use, "present but" immediately 1 resideual hearing was insufficient then a hearing aid would be line 5 before "insufficient". ineffectual. Consider replacing “insufficient” with “present.” Page 2, Recent Health We have made changes to There seems to be a grammatical problem here; it wasn’t the 1 Technology Assessment, reflect this edit. “guidelines” that conducted the additional analyses. lines 10-11 Methods Page 6, Comparator of consider defining “non-auditory support.” Also, the last sentence We have clarified this 1 Interest of this paragraph is unclear. statement. It is stated that “two-syllable or multi-syllable words are words Page 6, Outcomes of that have equal emphasis on both of them…” Not all two-syllable 1 Edited. Interest words have equally stress. It appears that this section is referring to a specific type of two-syllable words – spondees. Why wasn’t there consideration of perception of single-syllable words? I believe the assessment only found 2 studies that included two-syllable words. This is because those types of "Outcome measures were words are not often used in CI assessments. However, single chosen to respond to CMS' Page 6, Outcomes of syllable words are almost always included. They may be a more needs to assess day-to-day 1 Interest appropriate stimuli for uncovering binaural benefits as functional ability of subjects perception of single-syllable words occurs without the benefits of with cochlear implant." context that are provided by sentence-level stimuli. I find the lack of consideration of single-syllable word perception to be a limitation of this assessment. Page 6, Outcomes of Sensorineural hearing loss is not demonstrated by speech Corrected to “pre- 1 Interest, last sentence perception scores. implantation test scores” There is no justification for eliminating studies with sample sizes The clinical effectiveness of Page 6, Study designs less than 30 subjects. This would be helpful to the reader. I find unilateral cochlear 1 and sample size this factor to be an unfortunate one. Given the size of the implantation has been well population of CI users, one can expect small-scale studies. examined in prior systematic Further, many of the best CI research labs operate reviews. Sample size independently of CI programs that are most often located at thresholds were chosen medical centers. For this reason, is it not uncommon for papers based primarily on practical that come out of research labs to have studied smaller groups of consideration of available implant users. However, it is quite likely these studies are of resources and time balanced significantly higher scientific merit and that they could add very with the likely amount of important information and support to the central questions asked available literature. Including in the current assessment. I find the lack of inclusion of smaller- many more studies with scale, yet potentially well-executed, studies a limitation of this smaller sample sizes would assessment. have increased the number of subjects evaluated, but would very rarely upgrade to good methodological quality. I find much of this paragraph could benefit from some word- smithing. For example “distinguish speech at higher thresholds” Page 9, Candidates for is non-specific and could be misinterpreted. Another example is 1 Edited Cochlear Implants “ability to detect an audiometric pure-tone average…” Finally the parenthetical information in the second-to-last line of this paragraph is unclear. Page 12, Pre versus post 1 unilateral cochlear I find much of the second paragraph to be unclear. Deleted implants Page 19, 2nd line of last We have edited this 1 paragraph before Duration consider replacing “of” with “at” sentence of Impaired hearing The 2nd and 3rd sentences seems to contradict each other. The The sentence had been Page 20, Older Age, 2nd 2nd says there were no differences between younger and older 1 clarified. paragraph recipients while the 3rd sentences says that older patients had a significantly lower post-op score. I don’t see how these two sections differ – they are both looking "degree of pre-implant as preoperative speech perception/speech recognition or word hearing" has been changed Page 21, Preoperative understanding as a potential modifying factor postoperative to "degree of pre-implant Speech Perception Scores 1 speech perception or health-related quality of life outcomes. hearing as defined by pure & Degree of Pre-Implant Why wouldn’t they all be considered together? :Degree of pre- one thresholds. Therefore Residual Hearing implant hearing” perhaps needs better definition – is this just the two sections now are word perception or does it have to do with pure tone thresholds? mutually exclusive. The number was correct but Page 21, preoperative we had clarified the number 1 speech perception scores, is r=0.0003 really correct? was beta coefficient from last line multivariate regression. The immediate sequential second ear implant occurred What does “immediate sequential second ear implant mean? Is Page 30, study one month after first ear 1 this another way of saying simultaneous? If so, simultaneous characteristics, 4th line unilateral and we have would be much more clear to the reader. clarified the same in the text. Page 30, study characteristics, 9th line consider making “implant” plural. Done. from bottom Page 30, study results 4th 1 What was 100% compared to? Corrected. line from bottom Page 31, health-related 1 Last two sentences are unclear. Clarified. quality-of-life: Page 31, 5th line from The parenthetical (38%, P = 0.02) is hard to interpret. Is there We have made changes to 1 bottom some information missing here? clarify this sentence. Discussion/Conclusion Page 35, 1st full We have edited this 1 There are some grammatical problems here paragraph, 4th sentence sentence 1 Tables Though preoperative, contralateral scores are discussed in the literature, Isn’t there in indication that refers to “≤ 60% in the unimplanted our search did not reveal in 1 Table 1 ear?” the manufacturer's specifications of any indication with respect to the unimplanted ear. Due to time constraints, I did not take editorial notes on the We have proof-read the 1 Appendices content of the appendices. However, there were a couple of tables. instances that popped-out as needing some editing The ability to evaluate the effectiveness of a treatment, in this case cochlear implants in the adult population, is based on numerous factors not least of which is a baseline knowledge and understanding of the area to be studied. And a lack of real With peer review process, understanding can be reflected in the lack of clarity in the we think the clarity of the writing. I found that to be so in this document. While there is document would have much information included in the report, I had underlying sense improved. In general, 2 General that a ‘feel’ and true understanding of the subjective matter was leading publications with missing. positive findings get cited I found the choice of publications to include interesting. While I more frequently than the appreciate the group was attempting to hold to certain studies with negative and/or standards, the publications chosen were often not indicative of null findings. the leading publications in the field and therefore rather perplexing. While the conclusions were spot on, they did not seem to flow from the literature that was selected. The summary was understandable and succinct and reflected 2 Executive Summary Thank you. the document 2 Introduction/Background in sensorineural hearing all frequencies can be compromised to We have made changes to 2 Page 1, paragraph 2 various degrees depending on the type, degree of the hearing reflect this edit. loss.
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