Classification of magnitude of hearing loss (adapted from Clark, 1981; Anderson & Matkin, 1991)

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1 Diagnostic Classification Terms and Normative Data The following are agreed upon definitions to be used in clinical reports. However, full interpretation of audiological results should be made within the context of the entire evaluation including functional reports of hearing abilities. Classification of magnitude of hearing loss (adapted from Clark, 1981; Anderson & Matkin, 1991) Degree of Hearing Loss Hearing Loss Range (db HL) Normal -10 to 15 Slight (adults) 16 to 25 Minimal hearing loss (children) 16 to 25 Mild 26 to 40 Moderate 41 to 55 Moderately Severe 56 to 70 Severe 71 to 90 Profound 91 + Classification of audiometric configuration (ASHA, 2015) The configuration, or shape, of the hearing loss refers to the degree and pattern of hearing loss across frequencies (tones) as illustrated in a graph called an audiogram. For example, a hearing loss that only affects the high tones would be described as a high-frequency loss. Its configuration would show good hearing in the low tones and poor hearing in the high tones. On the other hand, if only the low frequencies were affected, the configuration would show poorer hearing for low tones and better hearing for high tones. Some hearing loss configurations are flat, indicating the same amount of hearing loss for low and high tones.

2 Classification of word recognition scores Note that this categorization system was developed by our clinic in the absence of an alternative, evidence based system Score in % Classification Magnitude of Problem Normal or None Excellent Good Mild. No difficulty in good listening conditions, some trouble in poor conditions Fair Moderate. Some trouble in good conditions, real trouble in poor conditions Poor Severe. Can just get along in good listening conditions Very Poor Extreme. Cannot rely on listening alone 0-20 Extremely Poor Complete. Hearing serves as a supplement to visual communication. SPRINT CHART for 25-WORD LISTS (Thibodeau, 2007) S e c o n d P T P A e r d c B e H n L t S c o r e First Percent Correct Score 95% Confidence Limit for PBmax on NU6 25-word list.plot score according to PTA on left ordinate and percent correct score on the abscissa. If it falls in the shaded area, it is considered disproportionately low. (Adapted from Dubno et al.,1995) 95% Critical differences for 25-word list. Plot first and second score according to the abscissa and right ordinate. If it falls within the arrow, the two scores are not significantly different (Adapted from Thornton & Raffin, 1978)

3 Classification of QuickSIN Scores Score in SNR Loss Classification Location of Directional Benefit 0-2 db Normal Very noisy environments Noisy environments 3-6 db Mild SNR Loss Quiet and minimally noisy environments 7-15 Moderate SNR Loss Quiet 15+ Severe SNR Loss Use of Pure Tone Averages The tradition in clinical audiology has been to use the pure tone average of thresholds at 500, 1000, and 2000 Hz for two different purposes. First, the pure tone average is compared to the speech thresholds as an indirect assessment of the intertest reliability. Second, the pure tone average can be utilized when classifying the degree or magnitude of the hearing loss (e.g. mild, moderate, severe, or profound). In cases with either normal hearing or those with a hearing loss having a relatively flat configuration, the three-frequency average is used for both of the purposes stated above. However, if the configuration of the hearing loss is either sloping or rising, the best twofrequency or Fletcher average is typically used to assess the reliability of the results. However, the impact of the hearing loss upon receptive communication is such cases may be underestimated if the degree or magnitude of the hearing loss is classified on the basis of the best two-frequency average ( Hz). Therefore, the following recommendations are made: 1. For comparison with the SRT, use the three-frequency average for flat losses or the twofrequency average for sloping, falling, or rising configurations as appropriate. If the discrepancy between the PTA and SRT is 12 db or greater, the inter-test reliability is judged to be poor suggesting a nonorganic hearing loss (Ventry & Chaiklin, 1965). Again, the slope of the hearing loss must always be taken into consideration. 2. Always use the traditional three-frequency average when classifying the degree or magnitude of the hearing loss regardless of the configuration. If the resulting classification (mild, moderate, etc.) seems inappropriate, use descriptive terms for the degree and configuration, rather than the traditional classification.

4 Classification of immittance findings (tympanometry and reflexes) 1. It is recommended that clinicians and students not describe the tympanogram by using the Jerger classification of Type A, B, C, etc. Instead, the results should be reported in narrative form. 2. With respect to middle ear pressure, the following guidelines and terminology are recommended: -50 to +50 dapa: Normal middle ear pressure -55 to -150 dapa: Slight negative pressure -155 to -250 dapa: Substantial negative pressure > -250 dapa: Excessive negative pressure The last two categories of substantial and excessive should be followed by a statement such as often associated with Eustachian tube dysfunction. 3. Compensated Static Admittance: recommended guidelines and terminology Normative Values (adapted from Tables 7.1 and 7.2 in Gelfand, 2016) Source 90% Normal Range (in mmhos) Adults Wiley (1989) Infants and Toddlers > 6 months Roush et al (1995) 6-12 months months months Calandruccio et al (2006) 6-12 months years Older Adults Golding et al (2007)

5 Suggested Terminology Admittance Description Type Type A Normal admittance Eardrum mobility was normal (see Table of norms above) Normal admittance with Eardrum mobility was normal with substantial Type C >-150 dapa pressure negative pressure suggesting Eustachian tube dysfunction Less than normative values Eardrum mobility was somewhat reduced Type As Greater than normative Eardrum mobility was significantly increased Type Ad values No measurable change in admittance with normal physical volume No measurable change in admittance with large physical volume suggesting a hypermobile TM Eardrum mobility was substantially reduced, a condition often associated with middle ear fluid Physical volume of ear canal was large, consistent with perforated TM or patent pressure equalization tube. Type B Type B 4. Acoustic reflex findings: recommended guidelines and terminology: Present at 100 dbhl or < present at expected levels Present at 100 dbhl or < present at reduced sensation levels With mild or moderate SNHL consistent with a cochlear disorder,(<65 db SL) Positive Reflex Decay Testing revealed acoustic reflex decay suggesting the possibility of a retrocochlear pathology.

6 References Anderson, K., Matkin, N. (1991) Relationship of Degree of Longterm Hearing Loss to Psychosocial Impact and Educational Needs. Co-authored by Noel Matkin. Educational Audiology Association Newsletter, 8,(1) and 8,(2). ASHA (2015) From: Configuration.pdf Calandruccio L, Fitzgerald TS, Prieve BA. (2007). Normative multifrequency tympanometry in infants and toddlers. J Am Acad Audiol, 17(7): Clark, J. G. (1981). Uses and abuses of hearing loss classification. ASHA, 23, Gelfand, S. (2016). Essentials of Audiology, 4 th ed. Thieme Medical Publishers, New York. Golding M, Doyle K, Sindhusake D, Mitchell P, Newall P, Hartley D. (2007). Tympanometric and acoustic stapedius reflex measures in older adults: the Blue Mountains Hearing Study. J Am Acad Audiol, 18(5): Roush J, Bryan t K, Mundy M, Zeisel S, Roberts J. (1995). Developmental changes in static admittance and tympanometric width in infants and toddlers. J Am Acad Audiol, 6(4): Thibodeau, L. M. (2007). Speech Audiometry. In R. Roeser, M. Valente, and H. Hosford-Dunn (Eds.), Audiology: Diagnostics (pp ). New York: Thieme Medical Publishers. Ventry IM, Chaiklin JB. (1965) Evaluation of pure tone audiogram configurations used in identifying adults with functional hearing loss. J Aud Res. 5, Wiley TL. (1989). Static acoustic-admittance measures in normal ears: a combined analysis for ears with and without notched tympanograms. J Speech Hear Res, 32(3):688.

SECTION 6: DIAGNOSTIC CLASSIFICATION TERMS AND NORMATIVE DATA

SECTION 6: DIAGNOSTIC CLASSIFICATION TERMS AND NORMATIVE DATA Revision: 8-17-2016 92 Diagnostic Classification Terms and Normative Data Classification of magnitude of hearing loss Normal 0 15 db HL Borderline