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Flashcards in Identification Audiometry Deck (18):
1

What is the primary goal of hearing screening programs? What is a disorder, impairment, and disablity? 

  • Primary goal of hearing screening programs:
    • to identify people with significant or potentially significant hearing problems (functional limitation)
      • Quickly ID people with hearing problems
  • Definitions (now antiquated): (WHO, 1980) 
    • Disorder: an abnormality of a structure or function
      • Damage to OHC
    • Impairment: physiological or psychological function is lost (i.e., a hearing loss)
    • Disability: the adverse effect of an impairment on a person’s ability to perform everyday tasks (work, school, social)
      • Impact
         

2

What does the WHO ICF classify? What are the lists?

  • Current WHO International Classification of Functioning, Disability and Health (ICF) (WHO, 2001)
    • Classification of health and health-related domains
    • Classified from body, individual, and society perspectives, from two lists:
      • Bodily functions and structures (includes “sensorial functions”; “ear structures”)
        • Auditory sensory function
      • Activity and participation (includes communication, interactions and personal relationships, etc.)
        • impact
    • A third list addresses environmental factors that affect functioning and disability (technology, environment, support & relationships, attitudes, services)
      • Society's ability to provide accommodation 

3

What are the specific goals of hearing screening for different populations?

  • Specific goals of hearing screening vary with the population tested: (note goals in relation to ICF classif) 
    • For newborns and infants:
      • identify children at risk for significant hearing impairment that can affect speech and language development (OAE and/or ABR screen)
      • Before screenings, high risk register missed 50% of significant hearing loss
    • For school-age children:
      • Identify children at risk for educationally significant auditory problems (hearing loss -> pure tone screen)
      • Identify children at risk for medically significant auditory problems (middle ear disease -> immittance screen) 
    • For adults
      • Identify adults with significant hearing impairment that can affect communication -> pure tone and “disability” (f’nal limitation) screen
         

4

What are the criteria for a screening test? What are the things that go into determining the cost of a screening program?

  • Acceptable: simple, interpretable, well-received by public
  • Reliable
  • Cost-effective (cost re:benefits)
    • Cost of equipment (C)
    • Lifetime of equipment (L)
    • Annual maintenance cost (M)
    • Salary of personnel (S) (the major cost)
    • Screening rate (number screened/hour) (R)
    • Number screened/year (N)
  • cost/child = S/R + [C + (M X L)/(N X L)]
  • Valid (sensitivity and specificity) 

5

What are the typical costs of school screenings?

  • N = 1,000 children
    • $0.43/child for audiometric screen
    • $0.46/child for immittance screen
  • N = 10,000 children
    • $0.29/child for audiometric screen
    • $0.19/child for immittance screen

6

What are sensitivity and specificity? What does it relate to? How is accuracy judged? What are the different outcomes? Give an example. What does high sensitivity and low specificity lead to? What does high specificity and low sensitivity lead to? 

  • Sensitivity: ability of screening test to accurately identify an abnormal ear (correct identification, or “hit”)
  • Specificity: ability of screening test to identify normal ears (correct rejection)
  • Relates to percentages of correct and incorrect results
  • Judge accuracy via a “gold standard”
    • for hearing screening - the pure tone audiogram
  • Example
    • Actual prevalence:
      • 9/40 are abnormal
      • Prevalence rate = 22.5%
    • Screening results:
      • 7 fail who are abnormal
      • Thus, correct rejection rate (sensitivity) is 7/9 = 78%
      • 27 pass who are normal
      • Thus, correct identification rate (specificity) is 27/31 = 87%
    • Want specificity and sensitivity to be as high as possible (trade-off)
  • High sensitivity and low specificity -> high overreferrals
  • High specificity and low sensitivity -> miss affected individuals
     

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7

What are screenings in public schools and newborn nursery mandated by? Senior citizen centers and health fairs?

  • In public schools (mandated by most states)
  • In newborn nursery (mandated by most states)
  • In senior citizen centers, health fairs, etc. (not mandated)  
    • Note: US Preventive Services Task Force recommendations on screening for ages >50 (Aug, 2012)

8

Describe hearing screenings in public schools. Since when have they been conducted? What do most states have? What does IDEA require? Who has the responsibility of the hearing screening program?

  •  Hearing screening conducted in US since 1929
    • Most states have hearing screening programs in public schools
    • Individuals with Disabilities Education Act (IDEA) in its regulations for students aged 3-21 years requires states to identify children with disabilities residing in the state.
    • Responsibility: designated by legislative mandate
      • Dept. of Public Health (medical follow-up)
      • Dept. of Education (educational follow-up)
         

9

Who are the personnel who run the hearing screening?

  • Personnel – who is responsible for conducting the hearing screening? (varies with child’s age)
    • **Audiologists or SLPs (administrators of program) 
    • Audiometrists, technicians, grad students (testing)
    • School nurses (organize program, coordinate followup)

10

Who should be screened (public school screening)? Who should be screened in public schools in the state of maryland?

  • Screen all children new to the school
  • Annual screening: 3 yrs through 3rd grade (because won't tell you if they think they can't hear well)
  • Screen at grades 7 and 11
  • Screen all children “at risk”
    • Concern about child’s hearing, speech, or language
    • Enrolled in special ed classes, repeating a class
    • Craniofacial or ear anomalies associated with hearing loss
    • History of late onset of hearing loss in the family
    • Signs of syndromes associated with hearing loss
    • Chronic or recurrent otitis media with effusion
    • Exposure to ototoxic drugs, or potentially harmful noise levels
    • Referred by classroom teacher for any reason
  • State of Maryland rules for hearing screening
    • Any child new to the school
    • All children entering the 1st grade, enters 4th, 5th, or 6th grade, and enters the 8th or 9th grade.
    • Additional screenings may be required under local board of education or health department policies
    • Students may be exempt from hearing screening if parent/guardian objects in writing on religious grounds.
       

11

What equipment is used in hearing screenings? How is it calibrated? What should the testing environment be?

  • Equipment: simple, sturdy, portable (1-2 lbs)
    • Performance characteristics should remain stable over time
  • Calibration:
    • Daily listening check  
    • weekly electroacoustic check
    • annual factory calibration
  • Environment: quiet room, carpeting, away from hvac (not expected to be sound-proof booth)
  • Allowable ambient noise levels - ambient noise may mask lower frequencies

12

What is the procedure for pure tone screenings acc to the ASHA guidelines? How many kids are tested in a room at a time? Where is the HL dial set to? How many students are screened at a time? How do they respond? How long should it take?  

  • ASHA Guidelines (1996)
    • 7 mos – 2 yrs: pure tone screening at 1k,2k,4k Hz
      • Use conditioned responses (VRA, CPA)
      • Testing under earphones
      • Test level: 30 dB HL using VRA; 20 dB HL using CPA
    • 3-5 yrs: 20 dB HL using conditioned play audiometry (1k, 2k, 4k Hz)
    • School age: 20 dB HL, using adult methods or CPA at 1k, 2k, 4k Hz
    • Adults: 25 dB HL screening level (1k, 2k, 4k Hz)
  • Test 10-20 children in room at a time
  • Give group instructions
  • Set HL to 20 dB HL
  • Screen 1 student at a time:
    • Right ear: 1k, 2k, 4k Hz -> switch ears
  • Student raises hand or finger
  • Should take 1 minute/child
  • Polished screener can check 150-200 children/day

13

What is described as a failure in a pure tone screening? What is required if a child fails? What happens if a child fails the rescreening? What procedures are conducted by the audiologist?

  • Failure: failure to respond at any 1 frequency in either ear
  • Mandatory re-screening in same session
  • Failure on re-screening -> referral for audiologic assessment
    • within one month (no later than 3 months)
  • audiologic eval: ac, bc, and speech in soundattenuating booth by qualified audiologist
     

14

Describe follow up procedures. What needs to occur for a referral to a medical doctor? What should the audiologist aim to do in terms of referrals? Do screening programs pick up on many issues? What are the state of MD rules? What else should the audiologist evaluate? Who should the results be reported to?

  • Each child identified must be followed-up
  • For child referred to audiologist: if significant hearing loss or air/bone gap -> refer to m.d.
  • ASHA guidelines:
    • HL> 25 dB HL between 250 – 2000 Hz*
    • HL> 35 dB HL between 4000 and 8000 Hz
    • Air-bone gap > 15 dB at 250 or 500 Hz  
    • Air-bone gap > 10 dB at 1000 Hz  
  • Want to minimize over-referrals
  • Screening programs do pick up many problems in children, despite hi false + rate
  • * State of MD rules are HL>25 dB HL at 1k, 2k, or 4kHz 
  • Evaluate educational implications for child identified with hearing loss
    • Improve special services for child (hearing aids, special seating, AR classes, auditory training, special classes, FM system)
    • Counsel parents re: hearing aids, special seating, classes for aural rehab and auditory training, other support services
    • Provide in-service classroom teacher training
  • Report results to parents, school, community     (document program results and individual results)
    • Reported to parents; parents are responsible for follow-up of child
    • Audiologist and m.d. complete form after exam -> child’s records
    • Results for individual children and school overall are kept in school files: results of screening, follow-up, personnel involved
    • Results for school reported to BOE and BOH

15

What did Wilson and Walton (1974) find about the effectiveness of the pure tone screening?

  • Wilson & Walton (1974)
    • Evaluated effectiveness of a school screening program similar to this one
    • N = 7,500 children
    • Procedures were 95% accurate:
      • 78% kids passed initial screen (22% failure rate)
      • 11.3% failed both screens 

16

Describe Dodd-Murphy, Murphy, & Bess's (2014) study on using 20 vs 25 dB HL for identifying children with MSHL. 

  • Dodd-Murphy, Murphy, & Bess (2014)
    • Retrospective study: compared the 2 levels for 1,475 children with known pure-tone thresholds (tested in mobile van; grades 3, 6, 9, 11)
    • Prospective study: screened 1704 children (grades 1, 2, 3, 5, 7)
      • Full evalon kids who failed the screen (25 dB HL) and a random sample who passed
      • Categorized audiograms into MSHL, NH, or Other
        • NH: all thresholds < 25 dB HL in both ears; Other: not NH nor MSHL
        • MSHL: bilateral hearing loss, PTA 20-40 dB HL in both ears, or high-frequency loss with ac Θs > 20 dB HL at 2 or more frequencies above 2kHz (1 or both ears), or unilateral HL with PTA > 20 dB HL in affected ear; no a-b gaps
      • Categorized screening results as pass, refer20, refer25
      • Prevalence of MSHL: about 4.9%, both studies, mostly unilateral hrg loss
      • Trade-off in specificity/sensitivity when changing screening level (sensitivity higher with 20 dB HL criterion; specificity higher with 25 dB HL)  
      • CONC: screening at 25 dB HL is inadequate for identifying kids w/ MSHL
         

17

Describe the epidemiology of hearing loss in children. What is the prevalence of hearing loss in children? What is the prevalence of significant bilateral hearing loss in newborns? What is the prevalence of middle ear disease in early childhood?

  • 5%-15% of children have reduced hearing levels in 1 or both ears, depending on criteria for hearing loss
  • Prevalence is higher among inner city, disadvantaged children
  • Prevalence of significant bilateral hearing loss in newborns: ≈ 1%
  • Prevalence of middle ear disease: very common in early childhood
    • 95% of all children have OM at least once by age 6
    • Most prevalent in children < 2 yrs (48% of population

18

Describe Shargorodsky, Curhan, Curhan, & Eavey's (2010) study on the prevalence of hearing loss in adolesents. What degree were most hearing losses? What what the prevalence of hearing loss of 25 dB HL or worse? What hearing losses were most common?

  • Examined prevalence of hearing loss among teenagers in 1988-1994 vs. 2005-2006
  • Found an increase in prevalence of hearing loss in recent survey
  • Recent estimate ≈ 20% of 12-19 year olds have hearing loss in US
    • Most hearing losses were slight
    • Prevalence of hrg loss > 25 dB HL was 5.3%
    • High frequency hearing loss and unilateral hearing loss were most common