DOES OAE/A-ABR HEARING SCREENING MISS HEARING LOSS? 2005 EDHI Conference Jean L. Johnson, DrPH Center for Disability Studies Director (Interim) March 3, 2005 Atlanta, GA

International Conference on Newborn Hearing Screening, Diagnosis and Intervention Cernobbio, Italy - May 2004 Second Annual Conference of the CDC Centers on Birth Defects and Developmental Disabilities Washington, DC – July 2004 Asia Region Neonatal Screening Conference Shanghai, China - September 2004 UH College of Education Research Symposium Honolulu, HI - October 2004 American Speech-Language and Hearing Association Philadelphia, PA – November 2004 CDC Ad Hoc Group – Teleconference January 11, 2005

Research Team Principal Investigator - Jean Johnson, DrPH Research Coordinator - Karl R. White, PhD Diagnostic Evaluation Coordinator - Judith E. Widen, PhD Site Co-Principal Investigators Judith Gravel, PhD Michele James, AuD Teresa Kennalley, MA Antonia B. Maxon, PhD Lynn Spivak, PhD Maureen Sullivan-Mahoney, MA Betty Vohr, MD Yusnita Weirather, MA

Funded by the Centers for Disease Control and Prevention CDC Consultants: June Holstrum, PhD Roy Ing, MD, MPH Brandt Culpepper, PhD Krista Biernath, MD Lee Ann Ramsey, BBA, GCPH under a Cooperative Agreement with: The Association of Teachers of Preventive Medicine with a sub-agreement to: The University of Hawai`i

Why is early identification of hearing loss so important? Hearing loss occurs more frequently than any other birth defect. Undetected hearing loss has serious negative consequences. Dramatic benefits are associated with early identification of hearing loss. It is true for severe to profound loss. Is it also true for milder hearing loss?

Background National Institutes of Health (NIH) Consensus Panel recommended in March 1993 that: “the preferred model for screening should begin with an evoked otoacoustic emissions test and should be followed by an auditory brainstem response test for all infants who fail the evoked otoacoustic emissions test.” Continuing improvement of ABR technology led to a number of hospitals in the US implementing a variation of the NIH recommendation that was based on automated ABR (AABR) Anecdotal reports to the Centers for Disease Control and Prevention (CDC) in the mid to late 1990’s that the two-stage OAE/AABR protocol was not identifying some infants with permanent hearing loss. The CDC issued a competitive Request for Proposals in 2000 to investigate whether the OAE/AABR screening protocol was not identifying babies with hearing loss.

Oto-Acoustic Emissions (OAE) Screening

Auditory Brain Stem (ABR) Screening

AABR Screening Comprehensive Hearing Evaluation Before 3 Months of Age Fail Pass Discharge OAE Screening Prior to Hospital Discharge Research Question Are infants with permanent hearing loss not being identified when newborn hearing screening is done with a two-stage OAE/A-ABR protocol in which infants who fail OAE and pass AABR are not followed? Study Sample Comprehensive Audiological Assessment at 8-12 months of age Comparison Group

Criteria for Selecting Sites 2,000 or more births per year Established newborn hearing screening program with at least six month history of success Historical refer rates of less than 10% for OAE and 4% for ABR Success in obtaining follow-up on 85% or more of referrals Ethnic and socio-economic distribution similar to US population

Participating Sites Name of Hospital Location Arnold Palmer HospitalOrlando, Florida Good Samaritan HospitalColumbus, Ohio Jacobi Medical Center New York, New York Kapi`olani Medical CenterHonolulu, Hawaii Long Island Jewish Medical SystemNew York, New York Via Christi Regional Medical CenterKansas City, Kansas Women & Infants HospitalProvidence, Rhode Island

Enrollment Process Eligible babies (Failed OAE and Passed A-ABR) were identified following newborn hearing screening. Parents were contacted and research study explained. Consent was obtained from families. Enrollment data was collected. Contact was maintained with family at 2, 4, & 6 months of age via post cards. Babies were seen for audiological diagnostic evaluation at 8-12 months of adjusted age.

Date Collected for Each Participating Baby BirthdateBronchio-pulmonary Dsplasia GenderMechanical Ventilation >7 Days Birth WeightECMO Gestational AgeNumber of Children in Home APGAR ScoresNumber of Adults in Home Days in NICU Total Household Income Malformations of the Head and NeckChild’s Race/Ethnicity Syndrome Associated with Hearing LossHealth Insurance In-utero InfectionsFamily History of Hearing Loss

Study Sample  1,524 Infants Enrolled  973 (63.8%) Returned for Evaluation  1,432 Ears Evaluated

Enrollment of Study Participants Enrollment Period Births During Enrollment Referral OAE Rate ABR Recruitment From Site #1 May 1, 2001 to Dec 31, ,6086.3%0.8%WB/NICU Site #2 June 1, 2001 to Jan 31, ,3934.5%0.9%WB/NICU Site #3 May 1, 2001 to Jan 31, ,0322.4%0.8%WB/NICU Site #4 Sep 20, 2001 to Jan, ,5098.0%1.0%WB Site #5 May 15, 2001 to Jan 31, ,2523.1%0.8%WB Site #6 May 1, 2001 to Jan 31, ,6235.3%1.2%WB/NICU Site #7 May 1, 2001 to Jan 31, ,2179.6%2.8%WB/NICU Total 86,6344.8%1.0%

Number of Babies: Births During Enrollment Eligible for Enrollment Total EnrolledNumber Not Recruited Number of Refusals Site # 1 16,6081, %18.3%40.0%41.7% Site # 2 9, %87.9%4.3%7.8% Site # 3 24, %37.3%2.4%60.3% Site # 4 4, %29.5%65.3%5.3% Site # 5 9, %70.3%14.4%15.3% Site # 6 6, %61.4%11.5%27.0% Site # 7 16, %48.2%11.6%40.2% Total 86,6343,4621, , %44.0%22.6%33.3% Enrollment of Study Participants (continued)

Audiological Diagnostic Evaluation Visual reinforcement audiometry (VRA) Tympanometry OAE - Either TOAE or DPOAE

VRA Protocol Protocol patterned after National institutes of Health Study (Norton, Univ. of Washington) Responses at 500, 1K, 2K, 4K Hz –Order of testing 2K,.5K, 4K, 1K –Aiming for minimal response level of 15 dB HL Multiple visits often necessary to complete testing –68% completed in 1 visit –24% required 2 visits –8% required 3 or more visits

CategoryCriteria Not Permanent Hearing Loss Using the ”best” results from all assessments, MRL thresholds of < 20dB at 1K, 2K, and 4K. Probable Not Permanent Hearing Loss Complete MRL data not available at 1K, 2K, and 4K, BUT *All frequencies had MRLs < 20dB OR OAEs within normal limits* OR Tone burst ABR data < 25dB. Permanent Hearing Loss (PHL) Sensorineural MRLs > 25dB at 1K, 2K, or 4K (tested with good confidence) OR ABR threshold > 30dB; AND if tested, OAEs below normal limits at the frequencies with elevated MRLs; AND normal middle ear functioning based on tympanometry or bone conduction. Permanent Hearing Loss (PHL) Conductive MRLs > 25dB at 1K, 2K, or 4K (tested with good confidence); AND if tested, OAEs below normal limits; AND bone conduction thresholds 15dB at frequencies with MRLs > 25dB. Increased Suspicion of PHL High Suspicion MRLs > 25dB at 1K, 2K, or 4K, BUT OAEs within normal limits for those frequencies OR only fair confidence in VRA testing. Some Suspicion* MRLs > 30dB at 1 frequency or > 25dB at more than one frequency, BUT abnormal tympanometry AND no bone conduction. * Sound field thresholds > 25dB (with fair confidence) AND normal tympanometry AND OAEs below normal limits. Not Sufficient Data to Rule Out PHL * No MRLs or OAEs within normal limits for 1K, 2K, or 4K and none of the above criteria for permanent hearing loss are met. * OAEs within normal limits were defined as > 3-6dB at 1K and > 6dB at 2K and 4K. Criteria for Categorizing Hearing Loss

# of Infants with Dx Data Percent of Infants w/ Dx Data Total Ears Not PHLPermanent Loss Hearing (PHL) Increased of Suspicion PHL: Probable Not PHL Not Sufficient Data SNHLPCHighSome Site # % Site # % Site # % Site # % Site # % Site # % Site # % Total % % % % 5 0.3% % % % % Hearing Status of Study Ears from All Hospitals

PHL in Comparison Group Sites (Fail OAE/Fail A-ABR)

PHL in Ears of Study Infants that Passed Initial OAE Ears of Study Infants that Passed Initial OAE Total EarsNot PHLPermanent Loss Hearing (PHL) Increased of Suspicion PHL: Probable Not PHL Not Sufficient Data SNHLPCHighSome Site # Site # Site # Site # Site # Site # Site # Total % % 0 0.0% 0 0.0% 8 1.6% 9 1.8% % %

Mild (25-40 dB) Moderate (41-70 dB) Severe through Profound (>70 dB) Total Infants Study Group % % 1 4.8% % Comparison Group % % % % Total % % /% % Degree of Hearing Loss in Study and Comparison Group Babies 80.3% 28.6% As measured in the worse ear

Comparability of Study and Comparison Groups What Percent of “Referred” Babies Did Sites Try to Follow? What Percent of “Followed” Babies Were Diagnosed? Study Group (Fail OAE/ Pass A-ABR) 44%64% Comparison Group (Fail OAE/ Fail A-ABR) 100%87% Reasonable to adjust prevalence rates for those who were not recruited Adjusting prevalence rates for differences in the percent of diagnostics completed is problematic Families who think their child has a hearing loss are more likely to return Families that are poor, single heads of household, transient, etc are less likely to return and these variables may be correlated with the incidence of hearing loss

How Many Additional Babies with Permanent Hearing Loss (PHL) were Identified? Comparison Group (Fail OAE/ Fail A-ABR) Study Group (Fail OAE/ Pass A-ABR) Total Number of Babies Prevalence per 1, *Adjusted for proportion of OAE fails that enrolled Represents 12% of all babies with PHL in birth cohort

Is it important that 21 Babies (30 ears) with PHL were found? How many does it add to what would have been identified otherwise? How many ears with hearing loss were found among those that passed the initial screen? How many babies would you have to follow to find 21 babies PHL? Is this congenital or late-onset hearing loss?

How many babies must be screened to find 21 with PHL? The obvious answer is 973, but…. This ignores that most screening programs that use OAE also do second stage OAE screen (usually following hospital discharge) Such outpatient screening is less expensive than the diagnostic protocol used in this study Difficulty of getting babies to return for outpatient screening must be considered

Screening Failures False Positives True Positives

Cost of Screening Direct cost Indirect cost Follow-up cost

Cost-Benefit of Screening Benefit COST Good follow-up Benefit COST Mediocre follow-up Benefit COST Poor follow-up

Were any of these ears late- onset losses? This study was not designed to answer that question. We do know that IF all of the ears with risk factors had been followed and identified, 9 of 21 babies would still have been missed Little is known about the incidence or what predicts late-onset hearing loss Most (>3/4ths) of the hearing losses “missed” were mild as was expected

Different Criteria for Determining Permanent Hearing Loss Comparison Group Study Group Total Based only on those meeting criteria for PHL (21 babies) 2.06 Including those categorized as high suspicion of PHL (33 babies) 2.49

Different Criteria for Determining Permanent Hearing Loss Comparison Group Study Group Total Based only on those meeting criteria for PHL (21 babies) 2.06 Including those categorized as high suspicion of PHL (33 babies) 2.49 X X X X

Variation Among Sites The study design assumed that sites are all equally well implemented To the degree that this isn’t true, data from some sites may be a better estimate of the number of babies being missed

# of Study Group Infants with PHL Average “Rank” for Implementa tion Quality of Site Births During Enrollment Period % and N of Eligible Infants Enrolled % and N of Refusals During Recruitment % Returning for Diagnostic Evaluations % with “Not Sufficient Data” Site # , % % %7.4% Site # , % % %0.8% Site # , % % %18.6% Site # , % % %9.1% Site # , % % %27.0% Site # , % % %7.1% Site # , % % %11.7% Indicators of Implementation Quality at Each Site PHL=permanent hearing loss

Presumed Curve of Health Care

Bell-Shaped Curve of Health Care

Best Estimate of Amount of PHL Missed by OAE/AABR protocol 12% of children with PHL in birth cohort 23% of children with PHL in birth cohort Babies Who Failed OAE / Failed AABR Babies who failed OAE/ Passed AABR Based on 44% that participated Adjusted for those who did not participate All Sites (.24 increase) 2.37 (.55 increase) Sites with Best Implementation (.48 Increase) 2.95 (.68 increase) 23% of children with PHL in birth cohort 17% of children with PHL in birth cohort

What’s the Best Estimate of the Number of Babies Missed by the OAE/AABR Screening Protocol? Depends on the criteria used for determining PHL Variation among sites Adjustments for Differences Between Study and Comparison Groups

Conclusions The OAE/AABR protocol, as implemented at these sites, failed to identify a substantial number of infants with PHL.  Best estimate is.55 per thousand or 24% of all infants with PHL.  Most were mild sensorineural hearing loss  Impossible from this study to determine how many are late-onset losses About 41% might be identified if all infants with risk factors or opposite refer ears were followed, but this is not likely.

Screening for permanent hearing loss should extend into early childhood (e.g. physician’s offices, early childhood programs). Emphasize to families and physicians that passing hospital-based hearing screening does not eliminate the need to vigilantly monitor language development. Screening program administrators should ensure that the stimulus levels of equipment used are consistent with the degree of hearing loss they want to identify. The relative advantages and disadvantages of the two- stage (OAE/A-ABR) protocol need to be carefully considered for individual programs. Recommendations

Prevalence and methods of identifying late-onset hearing loss Identification and monitoring of progressive hearing loss Ongoing investigation of sensitivity of various screening protocols and equipment (including what level of hearing loss is targeted) Practicality and cost-efficiency of alternative or additional “continuous” screening and surveillance techniques, especially in early childhood Further Research Recommendations

Questions to Ponder What degree of hearing loss do you want to identify? What cost will be required for that identification? Can you assure that follow-up will occur? What interventions can you provide? How can you provide continuing surveillance of late onset or progressive loss? How comfortable are you with the quality of services being provided?

Key Large-Scale Newborn Hearing Screening Studies in the United States Location/DatesCohort SizeNurseriesScreening Techniques Refer Rates Follow Up RatePrevalence Per 1000 of Hearing Loss RIHAP 3 (8/90 – 2/91) 1,850NICU & WBNOAE / ABR 26.9%73% 5.95 Colorado (1/92-12/96 27,938NICU & WBNAABR2.56 Rhode Island (1/93 – 12/95) 53,121NICU & WBNOAE / ABR 14.7% %a2.00 New Jersey (1/93 – 12/95) 15,749NICU & WBNABR 3% 3.3 overall 2.00 – WBN 13.0 NICU Hawai‘i (1/94 – 12/95) 9,605WBNOAE89%4.15 Texas (1/94 – 6/97) 54,228NICU & WBNOAE & AABR 3.5% 82.3%3.14 NIDCD ( ) 4,478 2,701 NICU & WBNABR- TOAE- DPOAE- 64.4% (Research) 56.0 New York (1/96 – 12/96) 69,761NICU & WBNOAE & AABR72%8.00 (NICU) 0.9 (WBN) Washington, DC (2/97 – 12/02) 39,437NICU & WBRTOAE 1.6% overall 1.9 WBN NICU ATPM/CDC (5/2001 – 1/2003) 86,634NICU & WBNOAE: 4.8 AABR: (Research)

Other Dissemination Article has been selected for publication in Pediatrics Five articles prepared for publication in American Journal of Audiology Presentation at Council on Exceptional Children Conference in Baltimore in April 2005.

Additional Information on Newborn Hearing Screening

Deafness separates people from people. --- Helen Keller