Identifying the severity level of unintelligibility objectively and efficiently holds critical clinical implications for speech assessment and intervention needs. The speech of children who demonstrate phonological deviations is frequently unintelligible. The use of an accurate and time-efficient measurement of intelligibility is necessary to screen children who may be producing phonological patterns that contribute to significantly reduced intelligibility in connected speech. The purpose of this study was to investigate the degree of concurrent validity between scores received on the 1-Minute Measure of Homonymy and Intelligibility (Hodson, 1992) and speech intelligibility as measured by the percent of words understood in connected speech. For this investigation, intelligibility is operationally defined as the percent of words understood in a connected speech sample derived from orthographic transcription. Data collected were from 48 children, aged 4:0 to 5:6, who demonstrated varying levels of phonological proficiency/deficiency. A group of four listeners who had experience treating children with phonological disorders were responsible for completing orthographic transcriptions of the 48 connected speech samples. The two methods of assessing speech intelligibility investigated in this study were found to correlate highly (r = .84). This is considered a significant statistical correlation and therefore the 1-Minute Measure may be used to provide speech-language pathologists with valuable information to predict a child's intelligibility level in connected speech. A regression formula was employed to predict percentage of intelligibility when presented with a child's 1- Minute Measure score. Results from this correlational study suggest that the 1- Minute Measure of Homonymy and Intelligibility may serve as an assessment tool that can provide a speech-language pathologist with some valuable information pertaining to a child's level of intelligibility in connected speech. When used with another speech assessment tool, the 1-Minute Measure may function as a screening measure to identify preschoolers who produce phonological deviations that interfere with intelligibility of conversational speech.

Speech-language pathologists are routinely called upon to make professional assessments concerning a speaker's level of intelligibility. The use of subjective judgement procedures for estimating a percentage of intelligibility is the general practice of many speech-language pathologists because they require minimal time. Although efficient, these methods lack any form of numerical support, and their validity and reliability is questionable. The standard within the field that provides data support is the orthographic transcription method, but it is considered to be too time-consuming for practical application (Samar & Metz, 1988). Researchers continue to seek a measure that is both valid and efficient to be used clinically. The purpose of this study was to establish validity of a check-slash transcription method used to provide objective numerical support for assigning percentage of intelligibility for individuals with moderate speech impairments. The study sought to answer the following questions: 1) Is the check-slash method of transcription a valid measure for quantifying percentage of intelligibility? 2) Is the check-slash method a more time-efficient procedure than the orthographic transcription method? The subjects for this study were 20 graduate students from Portland State University, that were randomly assigned to two transcription groups (check-slash or orthographic}. Each listener transcribed 12 samples taken from 2 girls and 10 boys between the ages of 4:1 and 5:6 with a moderate degree of phonological deficiency. The data were analyzed using individual Mann-Whitney U Tests for each of the 12 samples. Results indicated no significant difference between the check-slash and orthographic transcription methods when used to assign a percentage of intelligibility to individuals with a moderate speech deficit. Although no significant difference was found, interrater reliability for both methods was low. This study established efficiency for the check-slash transcription method when compared to the orthographic method. Increased efficiency for the check-slash method ranged from 38% to 54% over the orthographic method. Results may also indicate that listener perception may influence each clinician's ability to be accurate in their assessments.

Auditory processing is the ability of the brain to manipulate and utilise the neural output of the ear based on the frequency, intensity, and temporal features of the incoming acoustic signal. An auditory processing disorder (APD) is a deficiency in this ability. One category of tests that examine auditory processing ability are the various versions of the "filtered words test" (FWT), whereby a monaural, low-redundancy speech sample is distorted by using filtering to modify its frequency content. Due to the richness of the neural pathways in the auditory system and the redundancy of acoustic information in spoken language, a normal listener is able to recognize speech even when parts of the signal are missing, whereas this ability is often impaired in listeners with APD. One limitation of the various versions of the FWT is that they are carried out using a constant level of low-pass filtering (e.g. a corner frequency of 1000 Hz), which is prone to ceiling and floor effects. The purpose of this study was to counter these effects by modifying the FWT to use a computer-based adaptive procedure, to improve the sensitivity of the test over its constant-level counterparts. The University of Canterbury Monosyllabic Adaptive Speech Test (UC MAST) was performed on 23 normal adults, and 32 normal children (7 to 11 years of age). The child participants also underwent the SCAN-C test for APD in Children (Revised). Findings indicated a significant maturational effect on the UC MAST. Adult participants performed significantly better on the UC MAST in comparison to the child participants. In addition, adult participants performed the UC MAST more reliably than their younger counterparts. No correlation was found between performance on the UC MAST and SCAN-C test. The development of the UC MAST is discussed and the clinical implications of the findings are explored.

Hearing aid manufacturers commonly engineer automatic gain control (AGC) circuits which are aimed at reducing'sound tolerance problems and improving speech intelligibility among wearers. The most common type of AGC engineered is one utilizing a fast attack time. The present study was designed to evaluate the effects of both fast and slow attack times on the intelligibility of speech. Twenty-four normal hearing subjects listened to sixty pre-recorded sentences through two types of hearing aid circuits. Thirty sentences were modified by a fast attack AGC circuit, and thirty sentences were modified by a slow attack AGC. The subjects marked one of four multiple~choice answers for each sentence. The mean number of sentences answered incorrectly when heard through fast attack AGC was 8.25. When heard through slow attack AGC, the mean was 6.67. The performance differences which exist between these two modes of signal modification suggest that the fast attack does not improve intelligibility as significantly as slow attack time among normal listeners. Further investigation into the effects of slow attack AGC circuits on the user's ability to understand speech are recommended.

When the primary mode of communication is speech, the crucial ingredient for successful communication is intelligible speech. The speech of children with disordered phonologies is often unintelligible. Accurate and reliable measurement of speech with compromised intelligibility is essential if appropriate treatment procedures are to be chosen and implemented. The focus of this investigation was the measurement of speech intelligibility in young children. The purpose of this study was to investigate the relationship between the subjective method of trained ear estimation and the objective method of orthographic transcription when measuring the speech intelligibility of young speakers with a wide range of phonological profiency. For this study, the standard measurement of intelligibility was operationally defined as the percentage of words understood in a continuous speech sample derived from orthographic transcription of the sample. The secondary purpose was to investigate the accuracy of the speech-language pathologists' estimates as compared to the standard measure for each of the three groups: (a) the children with the most intelligibility, (b) with average intelligibility, and (c) with the least intelligibility. Data were collected from 47 children, aged 4:0 to 5:6, who comprised three groups with varying levels of intelligibility. Two groups of listeners who were unfamiliar with the speakers, but familiar with the topic, rated the children's percentage of intelligibility from continuous speech samples via orthographic transcription or trained ear estimation. The two methods of measuring speech intelligibility investigated in this study were found to correlate highly (£ = .96). However, there was a significant difference between the percentages derived from orthographic transcription and those derived from trained ear estimation for some speakers. The 1-test analyses revealed significant differences between the two measures for the two most intelligible groups, and no significant difference for the least intelligible group. It appears that the subjective method of estimating speech intelligibility with trained ears correlates with the objective method of orthographic transcription, but yields a different percentage score for some speakers.

Auditory processing disorder (APD) is a label that describes a variable set of symptoms that share a common feature of difficulty listening to sounds in the absence of an actual audiological deficit (Moore, 2006). Clinical assessment of APD typically involves a test battery consisting of tests designed to examine the integrity of various auditory processes of the central auditory nervous system. Individuals with APD have difficulty recognising speech when parts of the signal are missing. One category of tests used to assess the extent to which this deficit is associated with reduced performance on the task is the low-pass filtered speech test. The University of Canterbury Adaptive Speech Test-Filtered Words (UCAST-FW) is a computer-based adaptive low-pass filtered speech test developed for the assessment of auditory processing skills in adults and children. Earlier studies with the UCAST-FW (McGaffin, 2007; Sincock, 2008; Heidtke, 2010; Abu-Hijleh, 2011) have produced encouraging results. However, there appear to be a number of confounding factors. The UCAST-FW is testing New Zealand listeners using an Australian recording of American test material. The purpose of the current study was to develop a new four-alternative forced choice test to replace the Northwestern University Children’s Perception of Speech (NU-CHIPS) stimuli the UCAST-FW currently utilises. The new test consists of 98 sets of four test items, (one target item and three foil alternatives) designed to be used in a four-alternative forced choice picture-pointing procedure. Phonemic analysis of the new word list and the NU-CHIPS word lists revealed a similar distribution of phonemes for target words of both word lists. The development of the new word list is described and the clinical applicability is explored.

Auditory processing is the ability of the brain to manipulate and utilise the neural output of the ear based on the frequency, intensity, and temporal features of the incoming acoustic signal. An auditory processing disorder (APD) is a deficiency in this ability. One category of tests that examine auditory processing ability are the various versions of the "filtered words test" (FWT), whereby a monaural, low-redundancy speech sample is distorted by using filtering to modify its frequency content. Due to the richness of the neural pathways in the auditory system and the redundancy of acoustic information in spoken language, a normal listener is able to recognize speech even when parts of the signal are missing, whereas this ability is often impaired in listeners with APD. One limitation of the various versions of the FWT is that they are carried out using a constant level of low-pass filtering (e.g. a corner frequency of 1000 Hz), which is prone to ceiling and floor effects. The purpose of this study was to counter these effects by modifying the FWT to use a computer-based adaptive procedure, to improve the sensitivity of the test over its constant-level counterparts. The University of Canterbury Monosyllabic Adaptive Speech Test (UC MAST) was performed on 23 normal adults, and 32 normal children (7 to 11 years of age). The child participants also underwent the SCAN-C test for APD in Children (Revised). Findings indicated a significant maturational effect on the UC MAST. Adult participants performed significantly better on the UC MAST in comparison to the child participants. In addition, adult participants performed the UC MAST more reliably than their younger counterparts. No correlation was found between performance on the UC MAST and SCAN-C test. The development of the UC MAST is discussed and the clinical implications of the findings are explored.

Intelligible speech is a primary component for successful communication. However, the speech of children with disordered phonologies is often unintelligible. Therefore, when assessing the speech intelligibility of children in order to determine whether they qualify for intervention services, speech-language pathologists need reliable evaluation tools. The focus of this investigation was the measurement of speech intelligibility. The purpose of this study was to examine the relationship between two methods for measuring speech intelligibility. The first, identification method, involves the listener transcribing a speech sample from which the percentage of words understood is calculated. The second, scaling procedure, involves the listener estimating the percentage of words understood from a continuous speech sample. The secondary purpose of this study was to examine the accuracy of the scaling method as measured by ear estimation compared to the identification method as measured through orthographic transcription for each of three groups of children with: (a) the most intelligibility, (b) average intelligibility, and ( c) least intelligibility. Four unsophisticated listeners rated the speech intelligibility of 48 speakers aged 4:0 to 5:6 who comprised three groups with varying levels of phonological proficiency. The listeners who were unfamiliar with the speakers, but familiar with the topic, rated the children's continuous speech samples using ear estimation. The data collected were then compared with intelligibility ratings as measured in a previous study (Gordon-Brannan, 1994) via orthographic transcription. The two methods of measuring speech intelligibility examined in this study were found to be positively correlated (r = .86). However, the t-test analysis revealed significant differences between the two measures for the most and least intelligible groups, indicating discrepancies between the two methods when measuring the speech intelligibility of some children. Additional statistical analysis revealed poor intrajudge reliability which should be considered when interpreting the results presented. It does appear, however, that when measuring speech intelligibility, using ear estimation, is reflective of the orthographic transcription measure, although the actual estimated percentages of intelligibility appear to differ from the percentages derived from orthographic transcription.