The Effect of Varying Test Administration and Scoring Procedures on Three Tests of (Central) Auditory Processing Disorder.

BACKGROUND: There is currently no widely accepted objective method used to identify (central) auditory processing disorder ([C]APD). Audiologists often rely on behavioral test methods to diagnose (C)APD, which can be highly subjective. This is problematic in light of relevant literature that has reported a lack of adequate graduate-level preparation related to (C)APD. This is further complicated when exacerbated by the use of inconsistent test procedures from those used to standardize tests of (C)APD, resulting in higher test variability. The consequences of modifying test administration and scoring methods for tests of (C)APD are not currently documented in the literature. PURPOSE: This study aims to examine the effect of varying test administration and scoring procedures from those used to standardize tests of (C)APD on test outcome. RESEARCH DESIGN: This study used a repeated-measures design in which all participants were evaluated in all test conditions. The effects of varying the number of test items administered and the use of repetitions of missed test items on the test outcome score were assessed for the frequency patterns test (FPT), competing sentences test (CST), and the low-pass filtered speech test (LPFST). For the CST only, two scoring methods were used (a strict and a lax criterion) to determine whether or not scoring method affected test outcome. STUDY SAMPLE: Thirty-three native English-speaking adults served as participants. All participants had normal hearing (as defined by thresholds of 25-dB HL or better) at all octave band frequencies from 500 to 4000 Hz, with thresholds of 55-dB HL or better at 8000 Hz. All participants had normal cognitive function as assessed by the Mini-Mental State Examination. DATA COLLECTION AND ANALYSIS: Paired samples t-tests were used to evaluate the differences in test outcome when varying the CST scoring method. A 3 × 2 × 2 repeated-measures factorial analysis of variance (ANOVA) was used to determine the effects of test, length, and repetitions on outcome score for all three tests of auditory processing ability. Individual 2 × 2 repeated-measures two-way ANOVAs were subsequently conducted for each test to further evaluate interactions. RESULTS: There was no effect of scoring method on the CST outcome. There was a significant main effect of repetition use for the FPT and LPFST, in that test scores were greater when corrected for repetitions. An interaction between test length and repetitions was found for the LPFST only, such that there was a greater effect of repetition use when a shorter test was administered compared with a longer test. CONCLUSIONS: Test outcome may be affected when test administration procedures are varied from those used to standardize the test, lending itself to the broader possibility that the overall diagnosis of (C)APD may be subsequently affected.

Assessment of the efferent auditory system in children with suspected auditory processing disorder: the Middle ear muscle reflex and contralateral inhibition of OAEs.

OBJECTIVE: To determine whether children aged 7 to 12 years with listening difficulties show objective evidence for efferent auditory function based on measurements of medial olivo-cochlear and middle ear muscle reflexes. DESIGN: Click-evoked otoacoustic emissions recorded with and without contralateral broadband noise and ipsilateral and contralateral tonal (1000, 2000 Hz) middle ear muscle reflex thresholds were examined. STUDY SAMPLE: 29 children diagnosed with suspected auditory processing disorder (APD) and a control group of 34 typically developing children participated in this study. RESULTS: Children with suspected APD had poorer performance on auditory processing tests than the control group. Middle ear muscle reflex thresholds were significantly higher at 2000 Hz in the suspected APD group for contralateral stimulation. MOC inhibition effects did not differ between APD and control groups. CONCLUSIONS: This research supports earlier studies showing altered acoustic reflexes in children with APD. No group differences were found for the MOC reflex measures, consistent with some earlier studies in children with APD.

Impact of Personal Frequency Modulation Systems on Behavioral and Cortical Auditory Evoked Potential Measures of Auditory Processing and Classroom Listening in School-Aged Children with Auditory Processing Disorder.

BACKGROUND: Personal frequency modulation (FM) systems are often recommended for children diagnosed with auditory processing disorder (APD) to improve their listening environment in the classroom. Further evidence is required to support the continuation of this recommendation. PURPOSE: To determine whether personal FM systems enhance auditory processing abilities and classroom listening in school-aged children with APD. RESEARCH DESIGN: Two baseline assessments separated by eight weeks were undertaken before a 20-week trial of bilateral personal FM in the classroom. The third assessment was completed immediately after the FM trial. A range of behavioral measures and speech-evoked cortical auditory evoked potentials (CAEPs) in quiet and in noise were used to assess auditory processing and FM outcomes. Perceived listening ability was assessed using the Listening Inventory for Education-United Kingdom version (LIFE-UK) questionnaire student and teacher versions, and a modified version of the LIFE-UK questionnaire for parents. STUDY SAMPLE: Twenty-eight children aged 7-12 years were included in this intervention study. Of the 28 children, there were 22 males and six females. DATA COLLECTION AND ANALYSIS: APD Tests scores and CAEP peak latencies and amplitudes were analyzed using repeated measures analysis of variance to determine whether results changed over the two baseline assessments and after the FM trial. The LIFE-UK was administered immediately before and after the FM trial. Student responses were analyzed using paired t-tests. Results are described for the (different) pre- and post-trial teacher versions of the LIFE-UK. RESULTS: Speech in spatial noise (SSN) scores improved by 13% on average when participants wore the FM system in the laboratory. Noise resulted in increased P1 and N2 latencies and reduced N2 amplitudes. The impact of noise on CAEP latencies and amplitudes was significantly reduced when participants wore the FM. Participants' LIFE-UK responses indicated significant improvements in their perceived listening after the FM trial. Most teachers (74%) reported the trial as successful, based on LIFE-UK ratings. Teachers' and parents' questionnaire ratings indicated good agreement regarding the outcomes of the FM trial. There was no change in compressed and reverberated words, masking level difference, and sustained attention scores across visits. Gaps in noise, dichotic digits test, and SSN (hard words) showed practice effects. Frequency pattern test and SSN easy word scores did not change between baseline visits, and improved significantly after the FM trial. CAEP N2 latencies and amplitudes changed significantly across visits; changes occurred across the baseline and the FM trial period. CONCLUSIONS: Personal FM systems produce immediate speech perception benefits and enhancement of speech-evoked cortical responses in noise in the laboratory. The 20-week FM trial produced significant improvements in behavioral measures of auditory processing and participants' perceptions of their listening skills. Teacher and parent questionnaires also indicated positive outcomes.

Assessing Auditory Processing Abilities in Typically Developing School-Aged Children.

BACKGROUND: Large discrepancies exist in the literature regarding definition, diagnostic criteria, and appropriate assessment for auditory processing disorder (APD). Therefore, a battery of tests with normative data is needed. PURPOSE: The purpose of this study is to collect normative data on a variety of tests for APD on children aged 7-12 yr, and to examine effects of outside factors on test performance. RESEARCH DESIGN: Children aged 7-12 yr with normal hearing, speech and language abilities, cognition, and attention were recruited for participation in this normative data collection. STUDY SAMPLE: One hundred and forty-seven children were recruited using flyers and word of mouth. Of the participants recruited, 137 children qualified for the study. Participants attended schools located in areas that varied in terms of socioeconomic status, and resided in six different states. DATA COLLECTION AND ANALYSIS: Audiological testing included a hearing screening (15 dB HL from 250 to 8000 Hz), word recognition testing, tympanometry, ipsilateral and contralateral reflexes, and transient-evoked otoacoustic emissions. The language, nonverbal IQ, phonological processing, and attention skills of each participant were screened using the Clinical Evaluation of Language Fundamentals-4 Screener, Test of Nonverbal Intelligence, Comprehensive Test of Phonological Processing, and Integrated Visual and Auditory-Continuous Performance Test, respectively. The behavioral APD battery included the following tests: Dichotic Digits Test, Frequency Pattern Test, Duration Pattern Test, Random Gap Detection Test, Compressed and Reverberated Words Test, Auditory Figure Ground (signal-to-noise ratio of +8 and +0), and Listening in Spatialized Noise-Sentences Test. Mean scores and standard deviations of each test were calculated, and analysis of variance tests were used to determine effects of factors such as gender, handedness, and birth history on each test. RESULTS: Normative data tables for the test battery were created for the following age groups: 7- and 8-yr-olds (n = 49), 9- and 10-yr-olds (n = 40), and 11- and 12-yr-olds (n = 48). No significant effects were seen for gender or handedness on any of the measures. CONCLUSIONS: The data collected in this study are appropriate for use in clinical diagnosis of APD. Use of a low-linguistically loaded core battery with the addition of more language-based tests, when language abilities are known, can provide a well-rounded picture of a child's auditory processing abilities. Screening for language, phonological processing, attention, and cognitive level can provide more information regarding a diagnosis of APD, determine appropriateness of the test battery for the individual child, and may assist with making recommendations or referrals. It is important to use a multidisciplinary approach in the diagnosis and treatment of APD due to the high likelihood of comorbidity with other language, learning, or attention deficits. Although children with other diagnoses may be tested for APD, it is important to establish previously made diagnoses before testing to aid in appropriate test selection and recommendations.

Do children with reading delay benefit from the use of personal FM systems in the classroom?

FM systems have been used to compensate for poor signal-to-noise ratios in classrooms. This study evaluates benefits of a 6-week trial of personal FM systems used during the school day for children with reading delay aged 6-11 years, using a randomized control design. Teachers and children completed the LIFE-UK questionnaire. Test-retest reliability of the LIFE-UK children's version was confirmed in a separate group of 18 children from the same school. The 23 children in the FM group had significantly improved teacher ratings, and the children's ratings of classroom listening for difficult situations were significantly better after the trial. These changes did not occur for the 23 control-group children. Most children (92%) commented positively about the FM after the trial. It is likely that a longer FM trial or a specific reading intervention combined with FM will be required for the benefits of enhanced listening to affect performance on standardized reading tests.