Equal-appearing Interval Scale Research Articles

Usefulness of Direct Magnitude Estimation (DME) in Auditory Perceptual Assessments Measuring Dysphonia Severity

<h2>Summary</h2><h3>Objectives</h3> The purposes of this study were (1) to analyze the reliability of direct magnitude estimation (DME) scales in auditory perceptual assessments measuring dysphonia severity and (2) to analyze the usefulness of DME scales in comparison to that of equal-appearing interval (EAI) scales. <h3>Study Design</h3> Three speech language pathologists perceptually evaluated dysphonia severity from connected speech samples produced by 105 participants with dysphonia. Two auditory perceptual assessments using two scales (DME and EAI) were performed for 2 weeks. The reliabilities of auditory perceptual assessments were analyzed, and correlation analysis was performed to analyze the relationship between the two scales. <h3>Results</h3> DME and EAI were found to have high reliability for auditory perceptual assessments measuring voice severity. There was a significant curvilinear relationship between EAI and DME. This indicates that a prosthetic continuum represents the dysphonia severity and suggests that DME scales should be used to measure dysphonia severity to avoid the linear partitioning related to EAI scales. <h3>Conclusions</h3> Our study supports the use of DME scales when judging the overall voice severity of dysphonic patients.

Classification of heavy-weight floor impact sounds in multi-dwelling houses using an equal-appearing interval scale

Classifications of heavy-weight floor impact sounds based on subjective responses were suggested by conducting two experiments. First, statements describing perceptual acoustic qualities related to floor impact sounds in residential buildings were collected and assessed with respect to the degree of annoyance levels. Equal-appearing interval scaling for indicating level of annoyance caused by floor impact sounds was then created using these statements. As a next step, heavy-weight floor impact sounds with different LA,Fmax and temporal decay rates (DRs) were evaluated in terms of annoyance using both the Likert scale and the equal-interval statement scale in laboratory conditions. Five categories for heavy-weight floor impact sounds were suggested based on the annoyance responses. The extent of acoustic comfort in each class was clearly captured by the statements related to the range of LA,Fmax for each class. Effects of DR and noise sensitivity on the classifications were significant. Differences between the class criteria for impact sounds with DR 60 dB/s and 30 dB/s were approximately 5 dBA. In addition, significant differences were found between the high and low noise sensitivity classification groups for impact sounds in the 50–60 dBA range.

Using Ratings to Gain Insight Into Conceptual Development

The authors explored a novel technique with potential for assessing conceptual development. Participants rated how "normal" to "really weird" an image was in order to determine whether (a) participants would rate images by amount of variation (slight/significant) from the standard image, (b) participants would treat variation related to different concepts equally, or (c) there would be developmental differences in these ratings. Then, authors asked whether children with specific language impairment (SLI) would demonstrate weaker conceptual skills based on their ratings. Adults and school-age children (with and without SLI) used a 9-point equal-appearing interval scale to rate photographic images of animals. These included standard images and images that altered the animals' shape, pattern, color, and facial morphometry. Significant differences in ratings were obtained for adults compared with typically developing children and children with SLI compared with their age-matched peers. This is in line with the expectation that adults have stronger representations than children, as do typical children compared with those with SLI. Participants differentially rated images that varied from the standard image (slight/significant) for all parameters except shape. Probing conceptual representations without the need for verbal response has the potential for exploring conceptual deficits in SLI.

Development and perceptual assessment of a synthesizer of disordered voices

A synthesizer is based on a nonlinear wave-shaping model of the glottal area, an algebraic model of the glottal aerodynamics as well as concatenated-tube models of the trachea and vocal tract. Voice disorders are simulated by way of models of vocal frequency jitter and tremor, vocal amplitude shimmer and tremor, as well as pulsatile additive noise. Six experiments have been carried out to assess the synthesizer perceptually. Three experiments involve the perceptual categorization of male synthetic and human stimuli and one the auditory discrimination between synthetic and human tokens. A fifth experiment reports the auditory discrimination between synthetic tokens with different levels of additive and modulation noise. A sixth experiment reports the scoring by expert listeners of male synthetic stimuli on equal-appearing interval scales grade-roughness-breathiness (GRB). A first objective is to demonstrate the ability of the synthesizer to simulate vowel sounds that are valid exemplars of speech sounds produced by humans with voice disorders. A second objective is to learn how human expert raters perceptually map vocal frequency, additive and modulation noise as well as vowel categories into scores on GRB scales.

Vibratory and Perceptual Measurement of Resonant Voice

This study set out to investigate whether there existed a correlation between auditory-perceptual judgment of resonant voice and the physical vibration in the facial bone. The magnitude of bone vibration in the facial bone during different types of voice production (resonant vs nonresonant vs strained voices) was also investigated. Thirty-six healthy normal subjects produced three types of phonations: resonant voice, habitual nonresonant voice, and strained voice. A piezoelectric accelerometer was used to measure the vibrations in the nasal bridge and the perilaryngeal area during the phonation. Seventy-two selected nasal sounds (/ma/) produced under the resonant voice condition by these speakers were rated by two experienced speech pathologists on the magnitude of auditory-perceptual resonance using an 11-point equal-appearing interval scale. The magnitude of bone vibration was also compared across the three voice types. Significant moderate correlations were found between the physical bone vibration and the auditory-perceptual rating of resonant voice at the nasal bridge of the facial bone (0.6). Resonant voice, compared with the strained and nonresonant voice types, was also found to have a significant increase in the magnitude of facial bone vibration. Nasal stimuli, compared with nonnasal stimuli, facilitated greater bone vibration during resonant voice production. Piezoelectric accelerometer, as an objective quantitative tool, measures reliably the extent of bone vibration in resonant voice phonation. It is a useful tool for determining the bone vibration in relation to resonant voice.

Accent Assessment: A Preliminary Study of Scaling Validity

Direct Magnitude Estimations (DME) and Equal Appearing Interval (EAI) scaling techniques were used to compare listeners’ perceptions of the extent of accent from recorded speech samples of international students enrolled in a United States university who spoke English as a second language. Twenty five international students served as speakers by reading the same brief passage for recording purposes. Twenty five American-born students with no formal training or experience with accents or accent reduction rated the extent of the accent on each of the spoken samples using both scaling techniques. Statistical analysis of the listener’s perceptions indicated no significant differences between the DME or EAI scaling procedures and a scatterplot comparing the data sets for each technique produced a significant linear relationship between the data for the two techniques.

Effects of Consensus Training on the Reliability of Auditory Perceptual Ratings of Voice Quality

This study investigates the effect of consensus training of listeners on intrarater and interrater reliability and agreement of perceptual voice analysis. The use of such training, including a reference voice sample, could be assumed to make the internal standards held in memory common and more robust, which is of great importance to reduce the variability of auditory perceptual ratings. A prospective design with testing before and after training. Thirteen students of audiologopedics served as listening subjects. The ratings were made using a multidimensional protocol with four-point equal-appearing interval scales. The stimuli consisted of text reading by authentic dysphonic patients. The consensus training for each perceptual voice parameter included (1) definition, (2) underlying physiology, (3) presentation of carefully selected sound examples representing the parameter in three different grades followed by group discussions of perceived characteristics, and (4) practical exercises including imitation to make use of the listeners' proprioception. Intrarater reliability and agreement showed a marked improvement for intermittent aphonia but not for vocal fry. Interrater reliability was high for most parameters before training with a slight increase after training. Interrater agreement showed marked increases for most voice quality parameters as a result of the training. The results support the recommendation of specific consensus training, including use of a reference voice sample material, to calibrate, equalize, and stabilize the internal standards held in memory by the listeners.

Impact of a rapid palatal expander on speech articulation

Rapid palatal expanders (RPEs) have attachments cemented to the teeth and a screw that covers the palate. Because of their position and relative size, RPEs can affect speech. Our objective was to assess speech perturbation and adaptation related to RPE appliances over time. RPEs were planned for the treatment of 22 patients in the orthodontic clinic at the University of Toronto in Canada. Speech recordings were made at 6 time points: before RPE placement, after placement, during expansion, during retention, after removal, and 4 weeks after removal. The speech recordings consisted of 35 sentences, from which 3 sentences were chosen for analysis. Speech acceptability was assessed perceptually by 10 listeners who rated each sentence on an equal-appearing interval scale. The vowel formants for /i/ and the fricative spectra for /s/ and /∫/ were measured with speech analysis software. Repeated-measures analysis of variance with post-hoc paired t tests was used for statistical analysis. When the appliance was placed, speech acceptability deteriorated. Over time, the ratings improved and returned to baseline when the appliance was removed. For the vowel /i/, the first formant increased, and the second formant decreased in frequency, indicating centralization of the vowel. The formants returned to the pretreatment levels during treatment. For the fricatives (/s/ and /∫/), low-to-high frequency ratios indicated that the fricatives were distorted when the appliance was placed. The ratios returned to baseline levels once the appliance was removed. The results for the spectral moments indicated that spectral mean decreased and skewness became more positive. Repeated-measures analysis of variance showed significant effects for time for all acoustic measures. Speech was altered and distorted when the appliance was first placed. The patients' speech gradually improved over time and returned to baseline once the appliance was removed. The results from the study will be useful for pretreatment counseling of patients and their families.

The Dysphagia Handicap Index: Development and Validation

Quality-of-life indicators for dysphagia provide invaluable information to the treating clinician regarding the success or failure of swallowing therapy. The purpose of this study was to develop a clinically efficient, statistically robust patient-reported outcomes tool that measures the handicapping effect of dysphagia on emotional, functional, and physical aspects of individual's lives. 60 statements describing the handicapping effect of dysphagia were collected from patient reports and divided into subscales of physical, emotional, and functional problems. The statements were presented to 77 individuals with dysphagia. Respondents replied never, sometimes, or always to each statement and rated their self-perceived dysphagia severity on a 7-point equal-appearing interval scale. Cronbach's α was performed to assess the internal consistency validation of the items within the questionnaire. The final questionnaire was reduced to 25 items and administered to 214 individuals with dysphagia and 74 controls. Test-retest was performed on 63 individuals with dysphagia. Cronbach's α for the initial and final versions was strong at r=0.96 and r=0.94, respectively. Significant differences occurred between the dysphagia and control groups. Test-retest reliability was strong. We present a new, easy-to-complete, statistically robust, patient-reported outcomes measure for assessing the handicapping effect of dysphagia.

Toward a More Quantitative Measure to Assess Severity of Dysphonia Posttherapy: Preliminary Observations

The present research compares the efficacy of using the Dysphonic Severity Percentage (DSP) scale to the equal-appearing interval scale posttherapy. The initial pretherapy investigation was conducted to determine a more quantitative measure to rate the severity of dysphonia perceptually, because rating scales have shown considerable interrater variability. The posttherapy study is a follow-up to the initial research. The initial research involved counting the nondysphonic syllables in 10 participants with moderate-to-severe dysphonia (phonotrauma) to obtain a DSP during spontaneous speech and paragraph reading. The present posttherapy research used the same participants, the same raters, and the same method of assessment during spontaneous speech. The voice samples were both recorded and transcribed for simultaneous analysis and randomly presented to five raters, four of whom were experienced with voice disorders; one rater was a trained student. In this study, the dysphonic syllables were counted to obtain a DSP. As in the pretherapy investigation, the DSP in the posttherapy study was found to have high interrater reliability and to be a more quantitative perceptual assessment of voice than the interval scale. Additionally, the reliability of the difference scores between pre- and posttherapy results on the Cronbach's alpha was high on the DSP scale (0.901), but dropped to 0.506 on the interval scale. Moreover, the DSP rating scale yielded greater specificity in terms of vocal improvement posttherapy than the interval scale. The interval scale tended to mask the variation in vocal improvement among participants because of the limited choices presented.

The Relationship between Nasalance Scores and Nasality Ratings Obtained with Equal Appearing Interval and Direct Magnitude Estimation Scaling Methods

To assess the nasalance/nasality relationship and Nasometer test sensitivity and specificity when nasality ratings are obtained with both equal appearing interval (EAI) and direct magnitude estimation (DME) scaling procedures. To test the linearity of the relationship between nasality ratings obtained from different perceptual scales. STIMULI: Audio recordings of the Turtle Passage. Participants' nasalance scores and audio recordings were obtained simultaneously. A single judge rated the samples for nasality using both EAI and DME scaling procedures. Thirty-nine participants 3 to 17 years of age. Across participants, resonance ranged from normal to severely hypernasal. Nasalance scores and two nasality ratings. The magnitude of the correlation between nasalance scores and EAI ratings of nasality (r = .63) and between nasalance and DME ratings of nasality (r = .59) was not significantly different. Nasometer test sensitivity and specificity for EAI-rated nasality were .71 and .73, respectively. For DME-rated nasality, sensitivity and specificity were .62 and .70, respectively. Regression of EAI nasality ratings on DME nasality ratings did not depart significantly from linearity. No difference was found in the relationship between nasalance and nasality when nasality was rated using EAI as opposed to DME procedures. Nasometer test sensitivity and specificity were similar for EAI- and DME-rated nasality. A linear model accounted for the greatest proportion of explained variance in EAI and DME ratings. Consequently, clinicians should be able to obtain valid and reliable estimates of nasality using EAI or DME.

Measuring attitudes toward stuttering: English-to-French translations in Canada and Cameroon

Purpose A field test of a survey instrument under development, the Public Opinion Survey of Human Attributes, Experimental Edition (POSHA-E), designed to investigate language-, culture-, and nation-specific public opinions about stuttering is reported. This investigation compared English and French versions of the POSHA-E in widely disparate cultures to explore country versus language influences. Methods 120 experimental respondents rated POSHA-E items on 1–9 equal-appearing interval scales: 30 in English and 30 in French in both Canada and Cameroon. Comparisons were made with 30 matched, monolingual, American respondents in English only. Results Between-country differences for stuttering in experimental groups were much larger than between-language differences. Conclusions The POSHA-E can be translated to another language, i.e. French, without significant change in item meaning and interpretation in two divergent cultures, advancing the development and validity of an instrument that can be used in different language and cultural settings worldwide. Learning outcomes: Readers of this article should be able to describe the purpose of the Public Opinion Survey of Human Attributes (POSHA); describe translation and back-translation procedures for public opinion surveys to be used internationally; discuss cultural and linguistic differences between convenience samples from Ottawa, Canada and Douala, Cameroon; and compare the results of language versus country explanations of the results of this two-country investigation.

Variance in a Second Language Pronunciation Quality

The study assessed the relation between the overall degree of perceived foreign accent in non-natives' English speech and a variety of factors. Five native speakers of English were asked to auditorily evaluate the samples of free English speech produced by each of 99 non-native talkers using the equal-appearing interval scale. The 5-point scale was used to rate each of the variables for each non-native speaker and the interclass correlation coefficients were calculated to identify the most important predictors of foreign accent.

Some Extralingual Variables of L2 Phonic Competence

The study assessed the relation between the overall degree of perceived foreign accent in non-natives' English speech and some extralingual factors. These variables include musical ability, phonic mimicry ability and type of personality. Five native speakers of English were asked to auditorily evaluate the samples of free English speech produced by each of 79 non-native talkers using the equal-appearing interval scale. The 5-point scale was used to rate each of the variables for each non-native speaker and the interclass correlation coefficients were calculated to identify the most important predictors of L2 pronunciation quality. The findings reported may be important for the learning and teaching second languages.

Scaling Voice Activity Limitation and Participation Restriction in Dysphonic Individuals

The purpose of this study was to determine the most appropriate scaling procedure for evaluating voice activity limitation (AL) and voice participation restriction (PR). In a randomly counterbalanced design, 32 dysphonic individuals rated their self-perceived extents of voice AL and PR using two scaling procedures [equal-appearing interval (EAI) scaling and visual analogue (VA) scaling]. Results revealed that test-retest reliabilities were similar for the two scaling procedures. The overall extents of voice AL and PR obtained from the two scaling procedures were similar. Moreover, the significant linear relationships obtained between the EAI and VA data of voice AL and PR suggest both dimensions as metathetic in nature. Therefore, either EAI or VA scaling procedure would be considered as appropriate for rating voice AL and PR. However, the relative ease to use by consumers favours the choice of EAI over VA scaling procedure for evaluating voice AL and PR.

Reliability and confidence in using a paired comparison paradigm in perceptual voice quality evaluation

One of the ways to improve the reliability in perceptual voice quality rating is to provide listeners with external anchors. A paired comparison matching paradigm using synthesized Cantonese voice stimuli that covered a range of rough and breathy qualities were used to investigate the rating reliability. Twenty‐five speech pathology students rated the severity of roughness and breathiness of natural pathological voice samples using two paradigms: an eight‐point anchored matching (paired comparison) paradigm and an eight‐point non‐anchored equal‐appearing‐interval (EAI) scale paradigm. The listeners also rated their confidence in judging each testing stimulus on a seven‐point EAI scale. The results showed that the paired comparison method specifically improved the inter‐rater reliability in rating male rough stimuli and mildly dysphonic female stimuli. The intra‐rater agreement and confidence ratings remained similar across the two rating paradigms. These results suggest that the paired comparison paradigm may be used as an alternative perceptual voice quality evaluation tool.

Measurement of Speech Disfluency through Magnitude Estimation and Interval Scaling

The purpose was to assess whether equal-appearing interval or magnitude-estimation scaling resulted in a data set with a closer correlation to the physical stimuli, made up of speech samples with varying amounts of disfluency. 20 young adults completed two tasks. In Task 1, subjects used a 7-point equal-appearing interval scale to rate the disfluency of 10 speech samples having varying within sentence pause, presented randomly at 65 dB SPL. In Task 2, subjects used magnitude-estimation scaling to rate these stimuli, presented in a randomized order. Analysis showed significantly high correlations for both scaling techniques and the speech stimuli (Spearman rho=.90 and 1.00, respectively). It appears that subjects can use either scaling technique to rate accurately varied speech disfluency.

Scaling of Voice Pleasantness and Acceptability in Tracheoesophageal Speakers

The purpose of this study was (1) to determine the psychophysical character of auditory-perceptual ratings of voice pleasantness (VP) and voice acceptability (VA) for tracheoesophageal (TE) speakers using direct magnitude estimation (DME) and equal-appearing interval (EAI) scaling procedures and (2) to determine the relationship between listeners' ratings of VP and VA. Ten adult listeners judged overall VP and VA from connected speech samples produced by 20 adult male TE speakers. Although results yielded a prothetic continuum for VP and a metathetic continuum for VA, the amount of variance accounted for by a curvilinear model of VP was minimally more than that accounted for by a linear model. Results also revealed a significant relationship between VP and VA (r = 0.939). Findings from this study do not suggest any greater validity associated with VP and VA ratings obtained by the DME than the EAI method. As a result of the significant relationship between these ratings and to the ease of applying EAI scales, it is recommended that VA be used as a current clinical outcome measure. These data illustrate the need to identify attributes that best describe TE speech that are measured appropriately and are clinically useful.

Equal appearing interval and visual analogue scaling of perceptual roughness and breathiness

One of the factors that affects the reliability of perceptual voice evaluation is the rating scale. Equal‐appearing interval (EAI) and visual analogue (VA) scales are the two most common scales used and have attracted much attention in recent studies of perceptual voice evaluation. Available findings are contradictory, with one study finding the EAI scale to be more desirable while an earlier study showed equivocal results. The objective of the present study was to compare the reliability of using an 11‐point EAI scale and a VA scale, each of 10 cm long, for perceptual voice quality evaluation. Thirty listeners with no prior experience in perceptual voice evaluation were asked to rate the breathy and rough qualities of 28 voice samples. The results showed that the listeners demonstrated a significantly higher intra‐rater agreement and lower inter‐rater variability in rating the two perceptual voice qualities using the EAI scale, when compared to the VA scale. However, listeners tend to show more bias in using certain points on the EAI scale than on the VA scale. In addition, a linear relationship was found between the EAI and VA ratings, suggesting the psychoperceptual characteristics of breathy and rough qualities could be captured equally well by the EAI and VA scales. Since the ease of use of the rating scale is an important consideration in clinical situations, the 11‐point, 10 cm long EAI scale is therefore more preferable, although not necessarily more superior, than the VA scale for evaluating breathy and rough qualities.

Use of a Perceptual Evaluation Instrument to Assess the Effects of Infant Orthopedics on the Speech of Toddlers With Cleft Lip and Palate

Abstract Objective: To investigate the effects of infant orthopedics (IO) administered in the first year of life on the speech characteristics of 2.5-year-old children with complete unilateral cleft lip and palate (UCLP) using a perceptual evaluation instrument with equal-appearing interval (EAI) scales. Design: In a prospective randomized clinical trial (Dutchcleft), two groups of children with complete UCLP were followed longitudinally. One group received IO based on a modified Zurich approach (IO group), and the other group did not (non-IO group). The appliance was used until soft palate closure at age 12 months. Hard palate closure is delayed until 9 years of age. Participants: Three groups of 2.5-year-old toddlers participated in this investigation: 10 IO, 10 non-IO, and 8 noncleft controls matched for age and socioeconomic status. Method: Five trained listeners assessed the children's speech in a blinded perceptual rating procedure. They judged 13 specific speech characteristics and indicated their ...