ABSTRACT
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.
