Clinical Linguistics & Phonetics, October 2014; 28(10): 723–740 ß 2014 Informa UK Ltd. ISSN: 0269-9206 print / 1464-5076 online DOI: 10.3109/02699206.2014.892154

The role of language familiarity in bilingual stuttering assessment

AMANDA SAVIO LEE1, MICHAEL P. ROBB1, TIKA ORMOND1, & MICHAEL BLOMGREN2 1 2

Department of Communication Disorders, University of Canterbury, Christchurch, New Zealand and Department of Communication Sciences and Disorders, University of Utah, Salt Lake City, UT, USA

(Received 17 May 2013; revised 2 February 2014; accepted 4 February 2014)

Abstract The aim of this study was to evaluate the ability of English-speaking speech-language pathologists (SLPs) to evaluate stuttering behaviour in two Spanish–English bilingual adults who stutter (AWS1 and AWS2). The English-speaking SLPs were asked to judge the frequency, severity, type, duration, and physical concomitants of stuttering in both languages of the two AWS. The combined results from the Englishspeaking SLPs were then compared to the judgements of three Spanish–English bilingual SLPs. Results indicated that English-speaking SLPs (1) judged stuttering frequency to be greater in Spanish than English for AWS1, and equal in Spanish and English for AWS2, (2) were more accurate at evaluating individual moments of stuttering for the English samples compared to the Spanish samples, (3) identified fewer and less severe stuttering behaviours than the bilingual SLPs in both languages, and (4) were accurate judges of overall stuttering severity in both languages. The results correspond to past research examining the accuracy of stuttering evaluations in unfamiliar languages. Possible explanations for the findings, clinical implications, and future research directions are discussed.

Keywords: Assessment, bilingual, language, stuttering

Introduction Bilingualism is a continuum implying the use of two languages by an individual speaker. The individual may be equally proficient in both languages, as in the case of true balanced bilingualism, or, more commonly, may demonstrate a higher level of proficiency in one of the languages (Owens, 2005; Roberts, 2011). In its varying degrees, bilingualism is evident in millions of people throughout the world, who use more than one language in their daily lives. In fact, it has been estimated that more than half of the world’s population is now bilingual (Kohnert, 2007; Van Borsel, 2011). Consequently, SLPs are now encountering clients who are bilingual or multilingual with increasing frequency (Caesar & Kohler, 2007). In these speakers, the communication disorder will manifest in both or all of the languages, but may affect each to a different extent (Kohnert & Medina, 2009). It is well recognised that the clinical management of bilingual speakers with communication disorders presents a number of specific challenges and Correspondence: Amanda Savio Lee, Department of Communication Disorders, University of Canterbury, Private Bag 4800 Christchurch 8140, New Zealand. E-mail: [email protected]

724 A. S. Lee et al. considerations for SLPs, such as the need to develop and apply specialised knowledge concerning bilingual communication development, and to adapt ‘‘standard’’ assessment and intervention practices to take into account the client’s cultural and linguistic differences (Williams & McLeod, 2012). Particular care must be taken in differentiating linguistic difference from disorder in the assessment and diagnosis of these speakers, especially in light of the normal variation in linguistic ability across the languages of bilingual individuals (Kohnert & Medina, 2009). This issue has particular significance where the SLP and client do not share a common cultural and linguistic background, as is often the case (Williams & McLeod, 2012), and where the presentation of the communication disorder is not uniform across the languages of the bilingual speaker. There is a growing body of research that has examined the features of stuttering behaviour in bilingual speakers (Ardila, Ramos, & Barrocas, 2011; Chiam, 2013; Howell et al., 2004; Lim, Lincoln, Chan, & Onslow, 2008; Scha¨fer & Robb, 2012; Shenker, Conte, Gingras, Courcey, & Polomeno, 1998). The evidence suggests that in most instances, the frequency and severity of stuttering occurs differentially across the languages of bilingual adults who stutter (AWS). Most of the research in this area indicates a higher rate of stuttering in the less proficient language (L2)1 (Ardila et al., 2011; Lim et al., 2008; Scha¨fer & Robb, 2012). For example, Lim et al. reported a higher frequency of stuttering in L2 than L1 for 19 speakers of English and Mandarin (15 English–Mandarin and 4 Mandarin–English bilinguals). The authors found no differences in proportions of stutter types between L1 and L2. Scha¨fer and Robb observed more frequent stuttering in L2 than L1 for a group of 15 German–English bilingual AWS. Both Lim et al. and Scha¨fer and Robb suggested that their findings may be attributable to language proficiency. The greater cognitive and linguistic demands associated with the use of the less proficient language might place additional strain on the speech motor system, thus increasing the frequency of occurrence of speech disfluencies in that language. Scha¨fer and Robb also noted significant differences in the percentages of stuttering on function and content words in L1 versus L2, and interpreted this as evidence of a less mature form of stuttering in the less proficient language. That is, a pattern of disfluency characteristic of young children who stutter, rather than stuttering that persists into adulthood. In contrast, the opposite pattern of stuttering frequency distribution across the languages of bilingual AWS has also been observed, albeit less frequently (Howell et al., 2004). Howell et al. observed both a higher frequency and a more developed pattern of stuttering in L1 than L2, in a single case study involving a Spanish–English bilingual AWS. In attempting to summarise and explain the available literature in this area, researchers have highlighted the significant role of language-based and individual idiosyncrasies in determining patterns of stuttering behaviour in bilingual AWS (Ardila et al., 2011). It is also likely that some of the discrepancies in the literature on bilingual stuttering result from methodological variation across studies (Roberts, 2011). Due to the differential presentation of stuttering across languages in bilingual AWS, the clinical assessment of these individuals may be particularly problematic for many SLPs. The various linguistic, acoustic, and non-verbal characteristics of stuttering moments may be marked by language-specific features, and consequently masked to the ears of listeners unfamiliar with the language. Currently, it is not clear how SLPs’ stuttering judgements for a particular language are influenced by their familiarity with that language. Few studies have been conducted in this area,

1 In the literature, the terms ‘‘L1’’ and ‘‘L2’’ are typically used to refer to order of acquisition, in cases where the languages of bilingual speakers are developed successively (as opposed to simultaneously) (Owens, 2005). Depending on the language history of a bilingual speaker, order of acquisition may or may not correspond to level of proficiency (Owens, 2005). Within the current study, ‘‘L1’’ and ‘‘L2’’ refer to both order of acquisition and level of proficiency (i.e. L1 is the more proficient language) of the AWS speakers.

Bilingual stuttering assessment

725

and these have yielded mixed findings. For example, Einarsdottir and Ingham (2009) found that English-speaking SLPs were highly accurate in identifying samples of stuttered versus fluent speech in an unfamiliar language (Icelandic), and concluded that SLPs’ judgements of stuttering are generally language independent. Van Borsel and Britto Pereira (2005) asked panels of Brazilian and Dutch SLP students to judge fluent and stuttered speech samples from speakers of Portuguese and Dutch. Van Borsel and Britto Pereira found that the judges were generally able to accurately identify the speakers as normally fluent or stuttering speakers, regardless of language familiarity. For those speakers identified as AWS, the judges were also able to accurately rate the severity of the stuttering. However, when more specific information on the characteristics of the stuttered speech (e.g. stutter type, nature of physical concomitants) was requested, the SLP students provided more detailed responses for the speech samples in their native language, than in the unfamiliar language. This result indicates that the influence of language familiarity on accuracy of stuttering assessment may be more apparent for finer judgements of stuttering behaviour, than for broader judgements of overall severity. The students in Van Borsel and Britto Pereira’s study also reported that they felt less confident and experienced greater difficulty, when judging stuttering in an unfamiliar language. In another noteworthy report, Van Borsel, Leahy, and Britto Pereira (2008) observed a ‘‘closeness of language’’ influence on the accuracy of Dutch-, English-, and Portuguese-speaking SLP students’ stuttering judgements. The authors found that fluent speech was more likely to be mistakenly identified as stuttered speech (false positives), where the unfamiliar language was more dissimilar to the judges’ own native language. Both Dutch- and English-speaking students identified Dutch speakers as normally fluent or stuttering with comparable accuracy, but the Portuguese-speaking students performed significantly more poorly. Although Dutch, English, and Portuguese are all found within the Indo-European language family (Lewis, Simons, & Fennig, 2013), both Dutch and English belong to the West Germanic branch of languages, and are therefore closer to each other within the language tree than to Portuguese, which is a Romance language (Van Borsel et al., 2008). However, the panels’ judgements of stuttering severity, as well as their descriptions of specific stuttering characteristics, did not show a closeness of language effect. Nevertheless, Van Borsel et al.’s findings suggest that SLPs’ performance on stuttering assessment is not wholly language independent, but may be influenced by a diverse range of linguistic and task-related factors. Overall, the influence of language familiarity on SLPs’ ability to judge various characteristics of stuttering is unclear. Previous research (e.g. Van Borsel & Britto Pereira, 2005; Van Borsel et al., 2008) has focussed mainly on SLPs’ ability to make broad judgements on the presence or absence of the disorder in a given speaker, its overall severity, and its most salient characteristics. The current study was designed to contribute to the research in this area and to provide further clarity on the influence of language familiarity on stuttering assessment, both in terms of broad judgements of stuttering severity, and finer judgements concerning the specific characteristics (e.g. the location and type of individual stuttering moments, the duration of the longest stuttering moment, and the severity of physical concomitants) of the disorder. This range of general and more specific judgements is commonly required of SLPs in the real-world clinical context, for example, in the administration of the Stuttering Severity Instrument for Children and Adults – Fourth Edition (SSI-4; Riley, 2009). As such, data on SLPs’ ability to make these judgements accurately and consistently for bilingual AWS are highly relevant to SLP practice in this area. This topic is particularly important also in light of a significant bilingual and multilingual population of AWS, and the subsequent need to accurately assess, diagnose, and treat these individuals. The purpose of the present study was to compare the stuttering judgements of a group of English-speaking SLPs to the judgements of three expert Spanish–English bilingual SLPs.

726 A. S. Lee et al. Judgements were based on reading samples in both Spanish and English of two Spanish–English bilingual AWS. The following hypotheses were posed: (1) Spanish–English bilingual AWS will demonstrate a higher frequency of stuttering in L2 (English) than L1 (Spanish). (2) English-speaking SLPs will judge the overall severity of stuttering accurately in both the familiar (English) and unfamiliar (Spanish) language, in comparison to Spanish–English bilingual SLPs. (3) English-speaking SLPs will judge the specific characteristics of stuttering more accurately in the familiar language (English) than the unfamiliar language (Spanish), in comparison to Spanish–English bilingual SLPs. The characteristics of stuttering to be judged include: (1) the location and type of individual stuttering moments, (2) the most dominant stutter type (MDST) within the speech sample, (3) the length of the longest stuttering moment within the speech sample, and (4) the severity of physical concomitants.

Methods Participants The participants in this study were a group of 19 English-speaking SLPs (18 females, 1 male). The SLPs ranged in professional experience from 1 to 22 years, with a mean of 4.6 years. All of the SLPs had academic and clinical experience in the assessment and treatment of stuttering. However, none of the SLPs worked exclusively with AWS clients. Twelve of the SLPs reported that they were only proficient in English, with the remaining 7 participants reporting speaking proficiency in one or more other languages (i.e. Dutch, Mandarin, Bahasa Indonesia, Afrikaans, Cantonese, Malay, and Kannada). None of the SLPs was regularly exposed to Spanish, and none reported proficiency in any languages belonging to the same branch of the Indo-European language tree as Spanish (i.e. the Romance branch), such as Portuguese, French, or Italian (Lewis, Simons, & Fennig, 2013). All participants provided verbal and written consent prior to their involvement in the study. This study was approved by the University of Canterbury Human Ethics Committee. Procedures Speech samples Video-recorded speech samples from two Spanish–English bilingual AWS served as the stimulus material. The first bilingual AWS (AWS1) was a 16-year-old male who had acquired Spanish as L1, and later acquired English as L2 from the age of 5 years. He spoke English fluently, but with a Spanish accent. On a 5-point self-rating scale (very low, low, moderate, high, very high), he reported his proficiency in spoken English to be moderate or high. The second bilingual AWS (AWS2) was a 22-year-old female who had also acquired Spanish as L1. She later acquired English as L2 at 10 to 12 years of age, when her family migrated to the United States from South America. She spoke English with a strong Spanish accent. On the 5-point self-rating scale she reported her proficiency in spoken English to be very high. The video recordings were originally obtained from both AWS in the normal course of stuttering intervention. At the time, both participants gave written consent for the recordings to be made and used in stuttering research. Each AWS produced two readings of the first paragraph of The Rainbow Passage (Fairbanks, 1960), one in English, and one in Spanish

Bilingual stuttering assessment

727

(i.e. Leyenda del Arco Iris). Each passage contained approximately 100 words. Although monologue samples were used in previous research in this area (e.g. Van Borsel & Britto Pereira, 2005; Van Borsel et al., 2008), reading samples were used in the current study to control for linguistic variables across samples. For example, factors such as language content and linguistic complexity vary across samples of spontaneous conversation, which can affect stuttering frequency and characteristics (e.g. Hubbard, 1998; Silverman & Bernstein Ratner, 1997). The use of reading samples for which clear transcripts could be provided to SLP judges also helped in the elicitation of detailed judgements on stuttering characteristics. The reading samples were videorecorded in a quiet room, using a lapel microphone. Each sample was approximately 1 min in duration. In total, four reading samples served as the stimulus material for the current study (two participants  two reading samples). In addition, one video recording of a male Englishspeaking monolingual AWS reading the first paragraph of The Rainbow Passage was obtained. This recording was used as a practice sample for the SLPs. The purpose of the practice sample was to familiarise the SLPs with the use of the video stimuli and the procedures for recording their stuttering judgements, rather than to provide practice with judging stuttering in English and Spanish. None of the video clips contained speaker-identifying information. Stuttering judgement form For data collection purposes, the Stuttering Severity Instrument for Children and Adults – Third Edition (SSI-3; Riley, 1994) was adapted to produce the Stuttering Judgement Form (SJF). An example of the SJF is provided in the Appendix 1. The SJF was designed to facilitate consistent notation of stuttering severity and characteristics across SLPs, similarly to the SSI-3, and to elicit detailed information regarding individual moments of stuttering. This was to enable SLPs to make their stuttering judgements in a manner that was realistic and applicable to the clinical setting. The use of SSI-3 procedures and judgements also increased the validity and relevance of the study findings, as the SSI-3 (or SSI-4; Riley, 2009) is a commonly used measure of stuttering severity in both clinical and research contexts. Identification of specific characteristics of stuttering was included as part of the SJF to evaluate whether (1) language-specific differences would be apparent and (2) whether the English-speaking SLPs could accurately identify these characteristics of stuttering in an unfamiliar language. For each reading sample to be evaluated, a transcript of either The Rainbow Passage or Leyenda del Arco Iris was provided, as well as space for the SLPs’ stuttering judgements. Specifically, SLPs were required to: (1) Circle each syllable, word, or phrase on the transcript where they observed a moment of stuttering, and indicate the stutter type using the abbreviations provided. The ‘‘type’’ categories available were ‘‘Repetition’’ (‘‘Rep’’), ‘‘Audible Fixed Posture’’ (‘‘AF’’), ‘‘Inaudible Fixed Posture’’ (‘‘IF’’), ‘‘Interjection’’ (‘‘Int’’), and ‘‘Revision’’ (‘‘Rev’’). (2) Identify and underline the moment of stuttering within the sample that they perceived to be longest in duration. (3) Using a digital stopwatch, measure the duration of the stuttering moment identified to be longest in duration. The procedures for noting the length of longest stutter (LLS) judgement were taken directly from the SSI-3. (4) Identify the stutter type perceived to occur most frequently within the sample, termed the MDST. (5) Rate the physical concomitants of stuttering they observed within the sample, in the areas of ‘‘distracting sounds’’, ‘‘facial grimaces’’, ‘‘head movements’’, and ‘‘movements of the extremities’’. Each category of physical concomitants was rated for severity on a 6-point scale (where 0 ¼ none and 6 ¼ severe and painful-looking). Severity ratings across the four areas were then totaled to obtain an overall physical concomitants severity score.

728 A. S. Lee et al. The physical concomitants categories, rating scale, and scoring method paralleled those used for the SSI-3. (6) Rate the overall severity of stuttering within the sample, as ‘‘mild’’, ‘‘moderate’’, or ‘‘severe’’. This severity scale parallels that used for the SSI-3. Benchmark evaluation The speech samples were initially evaluated for stuttering severity and characteristics by three Spanish–English bilingual SLPs, all of whom spoke only Spanish and English, and were completely fluent in both languages. One of the bilingual SLPs was a native speaker of both Spanish and English, while the other two were native speakers of English who had lived extensively in Spanish-speaking countries. All three individuals had academic and clinical experience in the assessment and treatment of stuttering. Their professional experience in general SLP practice ranged from 2 to 20 years. The three Spanish–English bilingual SLPs completed the stuttering evaluations using the SJF, as per the data collection procedures outlined below. Their judgements were then combined to produce a composite standard of judgement, to which the English-speaking SLPs’ judgements were compared. For transcript-based stutter identification, the transcripts obtained from the bilingual SLPs were reviewed, and moments of stuttering for which there was at least 2/3 agreement (i.e. those syllables or words indicated as stuttered by at least two of the three bilingual SLPs) were identified. These were then transposed onto a composite standard transcript. The total number of stutters on each composite transcript served as the standard for the stutter count judgements. For stutter duration, most dominant type, and overall stuttering severity, all of which involved categorical judgements, 2/3 agreement was also used as the criterion for determining the ‘‘correct’’ response. On many of these judgements, perfect 3/3 agreement among the bilingual judges was observed, with at least 2/3 agreement successfully obtained in all instances. Finally, for the physical concomitants severity scores, ratings across the three bilingual SLPs were averaged to obtain mean scores, which were used as the standard for comparison. The bilingual SLPs were found to show considerable consistency in the majority of their English and Spanish stuttering judgements. Data collection All data were collected by the first author. Each SLP attended an individual data collection session, at a quiet location in the Department of Communication Disorders, University of Canterbury. Sessions lasted approximately 30–60 min, but were not timed. During the sessions, SLPs were seated in front of a computer screen, and provided with headphones, a digital stopwatch, and a copy of the SJF. Prior to beginning the task, SLPs were given verbal and written instructions on use of the video clips and completion of the SJF (see Appendix 1), as well as any necessary explanation of the abbreviations and terms used within the SJF. The SLPs were told to take their time with the task, and to view each reading sample as many times as necessary to make the requested judgements, using the available audio and video information. The task was then commenced, beginning with the practice sample. The order of the remaining four video clips was randomised for each participant. Each clip was viewed separately on the computer screen, using VLC Media Player, at the participant’s own pace. For each reading sample, SLPs recorded their judgements of stuttering severity and characteristics using the corresponding transcript and judgement pages of the SJF. The researcher was available to assist and provide clarification as needed, for the duration of the task. At the end of the session, the SJF was checked to ensure completion as per the instructions, and collected for data analysis.

Bilingual stuttering assessment

729

Data analysis The raw data from the completed evaluation forms were collated and analysed using one-sample t-tests and paired t-tests, to identify any statistically significant differences between (1) the English-speaking SLPs’ stuttering judgements and the bilingual SLPs’ stuttering judgements, and (2) the Spanish and English samples. Results Frequency of stuttering Descriptive statistics relating to the stuttering frequency judgements made by the SLPs are provided in Table 1. The mean numbers of stuttering moments identified by the English-speaking SLPs for each of the four reading samples, in comparison to those of the bilingual SLPs, are shown in Figure 1. For AWS1, the English-speaking SLPs identified more stuttering in L1 (Spanish) than L2 (English), which was in agreement with bilingual SLPs. For AWS2, the mean number of stutters identified by the English-speaking SLPs in both languages was identical. Again, this was generally in agreement with the bilingual SLPs. A one-sample t-test revealed that the English-speaking SLPs identified a significantly lower frequency of stuttering than the bilingual SLPs across all samples, regardless of language (p50.02). Table 1. Mean, median, standard deviation, and range values for the numbers of stutters identified by English-speaking (E-S) SLPs in each reading sample, in comparison to the bilingual SLPs. AWS1

Bilingual SLP judgement E-S SLP Mean E-S SLP Median E-S SLP Standard Deviation E-S SLP Range

AWS2

Spanish

English

Spanish

English

19 10.26 9 4.94 3–24

8 5.89 5 2.40 1–9

6 4.47 4 2.55 2–10

7 4.47 4 2.29 1–10

20 Bilingual SLPs 18

E-S SLP Average

Number of Stuers

16 14 12 10 8 6 4 2 0 (Spanish)

(English)

(Spanish)

AWS1

(English) AWS2

Reading Sample Figure 1. English-speaking (E-S) SLPs’ judgements of stuttering frequency for Spanish and English reading samples.

730 A. S. Lee et al. Overall stuttering severity The SLPs were required to assign an overall stuttering severity level to each of the reading samples. The severity levels available were ‘‘Mild’’, ‘‘Moderate’’, and ‘‘Severe’’. For each reading sample, the English-speaking SLPs’ judgements of overall severity were compared to the severity level identified by the bilingual SLPs. The percentage of English-speaking SLPs who assigned the same severity level as the bilingual SLPs was determined for each reading sample. For the Spanish reading samples, there was an average of 86% agreement between the Englishspeaking SLPs and the bilingual SLPs for judgement of overall stuttering severity. For the English reading samples, average agreement was 97%. A paired t-test revealed no significant difference in agreement levels between Spanish and English samples (p ¼ 0.5).

Stuttering characteristics Judgement of most dominant stutter type (MDST) The MDST was the stutter type that was judged to occur most frequently within each reading sample. The ‘‘type’’ categories available were ‘‘Repetition’’, ‘‘Audible Fixed Posture’’, ‘‘Inaudible Fixed Posture’’, ‘‘Interjection’’, and ‘‘Revision’’. The MDST judgements of the bilingual and English-speaking SLPs are shown in Table 2. The bilingual SLPs identified MDST as ‘‘Revisions’’ for the Spanish sample of AWS1, and ‘‘Inaudible Fixed Postures’’ for the remaining three samples. For each sample, the English-speaking SLPs’ judgements of MDST were compared to the MDST identified by the bilingual SLPs. The MDST categories of ‘‘Audible Fixed Posture’’ and ‘‘Inaudible Fixed Posture’’ were grouped for the purpose of MDST scoring. Therefore, where the bilingual SLPs identified MDST as ‘‘Inaudible Fixed Posture’’, ‘‘Audible Fixed Posture’’ was also accepted as a correct response. The percentage of English-speaking SLPs who were in agreement with the bilingual SLPs for the identification of MDST was determined for each reading sample. For the Spanish reading samples, an average of 47% (16% and 79% agreement for the two samples, respectively) of English-speaking SLPs were in agreement with the bilingual SLPs. For the English reading samples, an average of 75% (88% and 63% agreement for the two samples, respectively) of English-speaking SLPs were in agreement with the bilingual SLPs. A paired t-test revealed no significant difference in numbers of English-speaking SLPs who correctly identified MDST for Spanish versus English samples (p ¼ 0.66). Further inspection of the data revealed that for three of the four reading samples (two English and one Spanish reading sample), where MDST was identified by the bilingual SLPs as ‘‘Fixed Postures’’, between 63% and 88% of English-speaking SLP’s responses were consistent with this judgement. However, for the remaining one reading sample (Spanish), where MDST was identified by the bilingual SLPs as ‘‘Revisions’’, only 16% of English-speaking SLPs’ responses were consistent with this judgement. Judgement of individual stuttering moments Individual moments of stuttering were judged by ‘‘location’’ (i.e. the syllable or word within the reading sample on which the stuttering occurred) and ‘‘type’’ (i.e. ‘‘Repetition’’, ‘‘Audible Fixed Posture’’, ‘‘Inaudible Fixed Posture’’, ‘‘Interjection’’, or ‘‘Revision’’). Using the transcripts provided, SLPs were asked to indicate the approximate syllable or word of The Rainbow Passage on which instances of stuttering occurred, and to identify the stutter type for each instance. Responses were separately scored for accuracy on ‘‘location only’’ and ‘‘location and type’’ judgements for each stuttering moment, in comparison to the composite standard transcript derived from the individual transcripts of the three bilingual SLP judges.

Bilingual stuttering assessment

731

Table 2. English-speaking (E-S) SLPs’ judgements of most dominant stutter type (MDST) and length of longest stutter (LLS) in comparison to bilingual SLPs. MDST

LLS

AWS1 Bilingual SLP Judgement

Spanish Rev

E-S SLP Judgement 1 IF 2 Rep 3 Rep 4 Rep 5 IF 6 IF 7 Rev* 8 IF 9 Rep 10 IF 11 Rev* 12 Rep 13 Rev* 14 IF 15 Rep 16 Rep 17 AF 18 Rep 19 Rep

AWS2

AWS1

AWS2

English IF

Spanish IF

English IF

Spanish 51s

English 51s

Spanish 51s

English 41s

– IF* AF* AF* IF* IF* Rep AF* IF* IF* AF* IF* IF* IF* Rep – AF* AF* IF*

IF* IF* AF* AF* IF* IF* AF* Rep AF* IF* Rev IF* IF* IF* AF* IF* Rep Rep AF*

IF* IF* Rep IF* AF* Rep IF* Rep IF* AF* Rep IF* IF* AF* Rep IF* Rep AF* Rep

1s 1s 2s Half-s* Half-s* Fleeting* Fleeting* Half-s* 1s 3s 1s 2s 1s 3s 2s Half-s* 1s Half-s* –

Fleeting* Half-s* Half-s* Half-s* Fleeting* Fleeting* Fleeting* 1s Fleeting* Half-s* Half-s* Half-s* Half-s* 1s Half-s* Fleeting* Half-s* Half-s* Half-s*

Fleeting* 1s 1s Half-s* Fleeting* Fleeting* Fleeting* 1s Half-s* 1s 1s 1s Half-s* 3s 1s Fleeting* Half-s* Half-s* Half-s*

Half-s Fleeting 1s* Half-s 1s* Fleeting Half-s 1s* Half-s 1s* Fleeting Half-s Half-s 2s* 1s* Fleeting Half-s Half-s Half-s

AF Audible Fixed Posture. IF Inaudible Fixed Posture. Rep Repetition. Rev Revision. Fleeting 50.5s. Half-s 0.5–0.9s. 1s 1.0–1.9s. 2s 2.0–2.9s. 3s 3.0–4.9s. – No response. *Correct response.

The average level of agreement between the English-speaking SLPs and the bilingual SLPs for ‘‘location only’’, and ‘location and type’ judgements of individual stuttering moments was determined for the Spanish and English reading samples. Descriptive statistics relating to these agreement levels are shown in Table 3. Across the four samples, there was an average of 48% agreement for ‘‘location only’’ judgements, and 42% agreement for ‘‘location and type’’ judgements. Average agreement levels were 42% and 34% for the Spanish reading samples, and 54% and 51% for the English reading samples, for ‘‘location only’’ and ‘‘location and type’’ judgements, respectively. Paired t-tests revealed significantly higher agreement levels on ‘‘location only’’ judgements for the Spanish reading samples, the English reading samples, and the four samples combined (p50.001). Further, agreement levels were significantly higher in English than Spanish for both ‘‘location only’’ and ‘‘location and type’’ judgements (p50.005).

732 A. S. Lee et al. Table 3. Mean, median, standard deviation, and range values for the agreement levels between the English-speaking (E-S) SLPs and the bilingual SLPs on ‘‘location only’’ and ‘‘location and type’’ judgements in each reading sample. ‘‘Location only’’ judgements All samples E-S E-S E-S E-S

SLP SLP SLP SLP

Spanish

English

Mean (%) 48.05 42.01 54.09 Median (%) 50.00 42.11 53.57 Standard Deviation (%) 20.47 16.40 22.50 Range (%) 12.50–100.00 15.79–83.33 12.50–100.00

‘‘Location and type’’ judgements All samples 42.31 39.80 19.05 0.00–87.50

Spanish

English

34.10 50.52 33.33 50.00 14.34 19.74 0.00–66.67 12.50–87.50

Table 4. Mean, median, standard deviation, and range values for physical concomitants severity scores of the English-speaking (E-S) SLP judges for each reading sample, in comparison to the bilingual SLPs. AWS1

Bilingual SLP Judgement E-S SLP Mean E-S SLP Median E-S SLP Standard Deviation E-S SLP Range

AWS2

Spanish

English

Spanish

English

4.33 1.32 1 1.45 0–5

2.33 1.05 1 1.18 0–4

1.67 1.00 1 1.29 0–4

1.67 0.53 0 0.70 0–2

Judgement of length of longest stutter The SLPs were asked to approximate the length of the longest stuttering moment within each reading sample, using a digital stopwatch. The duration categories available for the LLS judgement were ‘‘Fleeting’’, ‘‘Half-second’’, ‘‘1 full second’’, ‘‘2 seconds’’, ‘‘3 seconds’’, ‘‘5 seconds’’, ‘‘10 seconds’’, ‘‘30 seconds’’, or ‘‘1 minute’’. For analysis of LLS evaluations, judgements of ‘‘Fleeting’’ and ‘‘Half-second’’ were grouped under the category ‘‘less than 1 second’’ (51s), while all remaining judgements were grouped under the category ‘‘more than 1 second’’ (41s). Therefore, where the bilingual SLPs identified LLS as ‘‘51s’’ (i.e. for AWS1 Spanish and English, and AWS2 Spanish), responses of ‘‘Fleeting’’ and ‘‘Half-second’’ by the English-speaking SLPs were both accepted as correct. The LLS judgements of all SLPs are shown in Table 2 above. For each reading sample, the English-speaking SLPs’ judgements of LLS were compared to those of the bilingual SLPs. The percentage of English-speaking SLPs who were in agreement with the bilingual SLPs for the judgement of LLS was determined for each reading sample. For the Spanish reading samples, there was an average of 47% agreement. For the English reading samples, there was an average of 61% agreement. A paired t-test revealed no significant difference in levels of agreement for Spanish versus English samples (p ¼ 0.80). Judgement of physical concomitants The SLPs were asked to score the severity of ‘‘Distracting sounds’’, ‘‘Facial grimaces’’, ‘‘Head movements’’, and ‘‘Movements of the extremities’’, for each reading sample, using a 6-point Likert-type scale (0 ¼ none; 1 ¼ not noticeable unless looking for it; 5 ¼ severe and painfullooking). Scores were then totaled across the four physical concomitants categories for each SLP and each reading sample. Descriptive statistics relating to the physical concomitants judgements made by the SLPs are provided in Table 4. The physical concomitant severity scores determined by the English-speaking SLPs for each reading sample, in comparison to the scores determined

Bilingual stuttering assessment

733

5 Bilingual SLPs 4.5 E-S SLP Average

Physical Concomitants Severity Score

4 3.5 3 2.5 2 1.5 1 0.5 0 (Spanish)

(English)

(Spanish)

AWS1

(English) AWS2

Reading Sample Figure 2. English-speaking (E-S) SLPs’ judgements of physical concomitants for Spanish and English reading samples.

by the bilingual SLPs, are shown in Figure 2. A one-sample t-test revealed that the physical concomitant severity scores of the English-speaking SLPs were significantly lower than those of the bilingual SLPs across all samples, regardless of language (p50.05). Discussion The SLPs who participated in the current study identified a significantly higher frequency of stuttering in Spanish than English for AWS1, and a similar frequency of stuttering across both languages for AWS2. This result was comparable to that of the bilingual SLPs, indicating that English-speaking SLPs are able to identify moments of stuttering and patterns of stuttering frequency in both a familiar (English) and an unfamiliar (Spanish) language. This finding is in agreement with past studies evaluating the role of language familiarity in SLPs’ judgements of stuttering moments (Einarsdottir & Ingham, 2009; Van Borsel & Britto Pereira, 2005). In the present study, AWS2 demonstrated a comparable frequency of stuttering in both L1 (Spanish) and L2 (English), which does not correspond to the original hypothesis of greater stuttering frequency in L2. The pattern of stuttering frequency exhibited by AWS2 is comparable to the trend observed for some English–Mandarin simultaneous bilinguals (Lim et al., 2008), which is surprising given that this individual reported a relatively late acquisition of L2 (10–12 years of age). However, AWS2 also reported her proficiency in spoken English to be ‘‘very high’’, so it is possible that she spoke both Spanish and English with native or near-native proficiency, and stuttered with equal frequency in both languages. Alternatively, the reading samples used in this study (containing approximately 100 words) may have been insufficient to accurately represent stuttering frequency in the languages of AWS2, particularly because a relatively low

734 A. S. Lee et al. frequency of stuttering was observed for this speaker. A conversational speech sample would have assisted in clarifying this matter. The trend towards higher stuttering frequency in L1 (Spanish) than L2 (English), which was observed in AWS1, was also contradictory to the original hypothesis. The prevailing view is that L2 is more vulnerable to moments of stuttering due to the bilingual AWS’ poorer proficiency in that language (Ardila et al., 2011; Lim et al., 2008; Scha¨fer & Robb, 2012). However, reports of bilingual AWS who demonstrate more frequent and more severe stuttering in L1 also exist (e.g. Howell et al., 2004). Howell et al. observed more frequent and more developed stuttering in L1 than L2 for a Spanish–English bilingual AWS. In attempting to explain these data, consideration should be given to certain speech- and communication-related factors thought to influence stuttered disfluency, which might also reasonably be expected to vary with language proficiency. For example, several theories have proposed that instances of stuttering result from the asynchronous operation of speech production processes, to which rapid speech motor execution is a contributing factor (Howell, 2004; Perkins, Kent, & Curlee, 1991). Since language proficiency is associated with confident, efficient speech delivery, and thus a higher speaking rate, a potential link between L1 and increased stuttering frequency is not inconceivable (Roberts, 2002; Van Borsel, 2011). L2 language users may speak more cautiously and with greater consideration, reducing the likelihood of speech production system asynchrony leading to stuttered disfluency. In a similar vein, the greater communicative spontaneity and self-expressive freedom characteristic of language proficiency might also produce more frequent stuttering in L1 for some AWS (Roberts, 2002; Van Borsel, 2011). Perkins et al. suggested that a necessary condition for stuttering to occur is the presence of conflict at the level of the ‘‘paralinguistic system’’, responsible for social-emotional language functions such as the basic expression of emotions and intentions. Greater vulnerability to such disruption may be inherent in L1 language use, whereas L2 use might naturally involve the more calculated production of linguistic content and structures. Further exploration of stuttering presentation across the languages of individual speakers is required to provide additional insight on these possibilities. It is interesting to note that three recent studies comparing stuttering in Spanish–English bilingual AWS have all observed a higher frequency of stuttering in Spanish (Ardila et al., 2011; Howell et al., 2004). In two of the three (Howell et al., 2004, and the present study), the bilingual AWS stuttered more in Spanish although they spoke it as L1, while in the remaining study (Ardila et al., 2011), the bilingual AWS spoke Spanish as L2. Both Howell et al. and Ardila et al. also observed a tendency towards a greater proportion of stuttering on content words in Spanish compared to English, a pattern which is indicative of more developed stuttering behaviour. Spanish and English both belong to the Indo-European language family; however, English is found in the West Germanic branch, whereas Spanish is a Romance language. It is possible that the phonetic and articulatory characteristics of spoken Spanish (or perhaps, of Romance languages in general) make it more vulnerable than English to more frequent and severe instances of stuttering. Howell, Au-Yeung, Yaruss, and Eldridge (2006) and Howell and Au-Yeung (2007) examined the relationship between stuttering and the phonetic characteristics of English and Spanish, respectively. The authors found that several factors contributing to phonetic complexity, including word length and presence of consonant clusters, differed in distribution between the two languages. For example, word length was a more frequent contributor to phonetic complexity in Spanish than in English, while the opposite pattern was observed for consonant clusters. Despite these differences in distribution, the same four major factors were found to be important determinants of stuttering in both languages: (1) place of consonant articulation, (2) manner of consonant articulation, (3) word length, and (4) consonant clusters (Howell & Au-Yeung, 2007). Although the cumulative effect of the different complexity factors on stuttering in each language has yet to be examined, these findings do suggest a relationship between stuttering and the features

Bilingual stuttering assessment

735

of a specific language, which, in bilingual AWS, may interact with the L1 or L2 status of that language for a given speaker. In addition to the unique interactions between the features of stuttering behaviour and those of any given language, there may be other factors contributing to the observed differences in stutter frequency. First, the available literature is characterised by methodological variations. Studies employ small participant pools (indeed, many of the reports are based on single cases), so that the findings cannot be easily generalised. Second, as demonstrated by the differences in patterns of stuttering frequency observed for AWS1 and AWS2, individual idiosyncrasies may significantly influence patterns of stuttering behaviour in bilingual AWS (Ardila et al., 2011). Bilingualism is not a static, homogenous construct, but a dynamic continuum (Kohnert, 2007; Owens, 2005; Roberts, 2011). The speech, language, and stuttering behaviour (both physical and psychological aspects) of any bilingual AWS is unique, and this complicates any attempt to draw general conclusions about the relationship between these variables. Ultimately, there remain many questions unanswered, and further study is needed to shed more light on this area. In the current study, the accuracy of the English-speaking SLPs’ stuttering evaluations was determined by comparing their judgements of both the Spanish and English reading samples to those of three Spanish–English bilingual SLPs. Based on past research (Van Borsel & Britto Pereira, 2005), it was hypothesised that the English-speaking SLPs would be able to judge the overall severity of stuttering accurately in both Spanish and English, but would judge specific characteristics of stuttering more accurately in the familiar language (English) than the unfamiliar language (Spanish). With regard to overall severity, it was found that the English-speaking SLPs’ judgements in both Spanish and English were generally consistent, and in agreement with the bilingual SLPs. This result indicates that English-speaking SLPs are able to judge overall stuttering severity both in a familiar (English) and an unfamiliar (Spanish) language, and corresponds to earlier reports on stuttering judgement and language familiarity (Einarsdottir & Ingham, 2009; Van Borsel & Britto Pereira, 2005). The findings are encouraging, suggesting that SLPs may be competent in forming accurate diagnostic statements even for stuttering clients from culturally and linguistically diverse backgrounds. On the other hand, the third hypothesis of the present study predicted that language familiarity would affect the English-speaking SLPs’ judgements of specific stuttering behaviours. This was found to be the case for some, but not all, of the comparisons. Agreement between the Englishspeaking SLPs and the bilingual SLPs on judgements concerning specific instances of stuttering was generally low to moderate, indicating poorer inter-rater reliability at this level of assessment. The English-speaking SLPs did judge individual instances of stuttering more accurately in English compared to Spanish, in terms of both ‘‘location only’’ and ‘‘location and type’’ judgements, indicating the presence of a language familiarity effect. This result is contrary to previous findings that accuracy of stuttering assessment is language independent (Einarsdottir & Ingham, 2009; Van Borsel & Britto Pereira, 2005). It must be noted that none of the earlier studies required their participants to make fine judgements of individual stuttering moments at the level examined in the current study. Indeed, Van Borsel and Britto Pereira reported the observation that SLP students were able to describe stuttering characteristics in greater detail when assessing stuttering in a familiar language, which complements the finding in the current study that these detailed judgements do exhibit a language familiarity effect. In addition, in this study it was observed that agreement on ‘‘location only’’ judgements was significantly higher than on ‘location and type’ judgements, for each language as well as for both languages combined. This result is perhaps unsurprising, because inter-rater agreement on two points of judgement would logically be more difficult to achieve than on a single point. However, despite the statistical significance of the differences observed, it may be suggested that agreement levels between the English-speaking SLPs and the bilingual SLPs for ‘‘location only’’

736 A. S. Lee et al. and ‘‘location and type’’ judgements (48% and 42% for all samples combined, respectively) did not in fact differ to a practically or clinically significant extent. That is, poor inter-rater reliability featured primarily at the basic level of stutter identification (i.e. specifying the syllable or word comprising the stuttering moment). Once a moment of stuttering was accurately identified, it was most likely also to be described correctly in relation to its type characteristics. This finding implies poor agreement among SLPs on the fundamental question of what, perceptually and practically speaking, constitutes an instance of stuttering. Although the integrity of broad stuttering judgements appears not to be compromised by this fact, an improved perceptual definition of stuttering would facilitate greater rater agreement on the presence or absence of specific moments of stuttering, which would clearly be helpful particularly for research purposes. The SLPs were also required to identify the MDST for each sample. Where MDST was a disfluency type clearly characteristic of disordered speech fluency (i.e. ‘‘core’’ stuttering behaviours, such as fixed postures), the English-speaking SLPs were found to be relatively consistent for both Spanish and English samples and in agreement with the bilingual SLPs. The English-speaking SLPs made less accurate, more varied judgements of MDST where MDST (as identified by the bilingual SLPs) was a disfluency type more characteristic of typically fluent speakers (i.e. ‘‘other’’ disfluencies, such as revisions). On the basis of this observation, it appears that SLPs’ ability to characterise stuttering types may be more dependent upon the dominant type of disfluency manifested by a particular speaker, than on language familiarity. This is reasonable, especially in the light of self-report evidence that SLPs give greater weight to core stuttering behaviours in judging stuttered speech, than to other types of speech disfluencies, regardless of language familiarity (Van Borsel & Britto Pereira, 2005). A second explanation for this finding is that the terminology used in this study to refer to ‘‘other’’ disfluencies (i.e. ‘‘revisions’’ and ‘‘interjections’’) was not sufficiently specific, or was interpreted differently by the bilingual judges and English-speaking SLPs. Although instructions and examples relating to the disfluency types were provided to each participant prior to commencement of the judgement task, it is still possible that the SLPs may have applied the disfluency type terms inconsistently, thus producing variability in the MDST judgements. Interestingly, the English-speaking SLPs judged stuttering to be less frequent and less severe than the bilingual SLPs, for both Spanish and English reading samples. Specifically, the Englishspeaking SLPs identified significantly fewer moments of stuttering than the bilingual SLPs, and reported significantly lower physical concomitant severity scores than the bilingual SLPs, across both Spanish and English reading samples. This observation was surprising as the Englishspeaking SLPs were expected to perform comparably to the bilingual SLPs, at least in the language familiar to them. In addition, it is unlikely that the results were influenced by the clinical experience levels of the raters involved, because a wide range of experience levels were represented among both the English-speaking SLPs (1–22 years) and the bilingual judges (2–20 years). All raters had academic and practical experience with stuttering, and none worked exclusively with AWS clients. Instead, it is possible that these particular stuttering judgements were influenced by suprasegmental features of language, namely, accent. The two AWS speakers used in the present study spoke Spanish as L1 and English as L2. That is, the AWS participants spoke Spanish and Spanish-accented English. This may have served to mask the characteristics of stuttering in the bilingual speakers, as a result of the English-speaking SLPs’ lack of familiarity with Spanish-accented English. Alternatively, the English-speaking SLPs may have identified fewer stutters and less severe physical concomitants across both languages due to more cautious judgement or a lack of confidence, by the simple fact that they were assessing stuttering in bilingual AWS. Indeed, there is evidence in the form of self-report data to show that SLP students feel less confident and perceive greater difficulty when judging stuttering in foreign language speakers (Van Borsel & Britto Pereira, 2005).

Bilingual stuttering assessment

737

Finally, the English-speaking SLPs were unreliable judges of stuttering duration, regardless of language familiarity. Their judgements of LLS varied widely and reflected a low to moderate level of agreement with the bilingual SLPs, across both Spanish and English samples. This result suggests that there may generally be low inter-rater reliability among SLPs in this area of stuttering assessment, even where judgements are made in the SLPs’ own native language. However, the finding of the current study is markedly different to those of several earlier studies on the reliability of the SSI-3 measure, which observed a high level of inter-rater agreement on the duration judgement component of the SSI-3 assessment, when completed for monolingual speakers (Bakhtiar, Seifpanahi, Ansari, Ghanadzade, & Packman, 2010; Riley, 1972). It is important to note that the current study did not utilise the SSI-3 as such, but adapted it to produce an assessment tool suited to the needs of the study. Still, it would seem that additional research is needed to explore the linguistic and clinical contexts in which duration judgements do (and do not) represent a reliable and useful component of stuttering assessment. Clinical implications The English-speaking SLPs’ descriptive ratings of overall stuttering severity, identification of patterns of stuttering frequency across Spanish and English, and identification of MDST, were generally consistent and in agreement with the bilingual SLPs. However, the specific identification and description of individual moments of stuttering were less accurate and less reliable among the English-speaking SLPs. The findings indicate that broad judgements of stuttering severity, frequency, and type may not be significantly influenced by language familiarity factors. These results agree with the available data in this area (Einarsdottir & Ingham, 2009; Van Borsel & Britto Pereira, 2005; Van Borsel et al., 2008), and suggest that SLPs can accurately assess and diagnose stuttering in clients from culturally and linguistically diverse backgrounds. However, it must be noted that the stuttering judgements completed by the SLPs in the current study were based on samples of reading (as opposed to spontaneous language), which limits the generalisability of the findings. In addition, it would be prudent to keep in mind that finer characteristics of the disorder may be obscured in an unfamiliar language (and potentially even where a language is familiar, but accented by a speaker’s L2). Where specific judgements of stuttering severity and characteristics might play a decisive role in the disorder’s management, it would therefore be wise to seek the assistance of an individual fluent in the languages of the AWS. Finally, the contribution of duration judgements to stuttering assessment should also be viewed with some degree of caution, until further evidence on the reliability and usefulness of this measure becomes available. Acknowledgements The authors would like to acknowledge the bilingual SLP judges – Lucia Habanec, Eliza Hintze, and Chris Fidler – for their contributions to this study. The authors also thank Dr Maria Diana Gonzales for her input. Declaration of interest The authors report no conflict of interest.

References Ardila, A., Ramos, E., & Barrocas, R. (2011). Patterns of stuttering in a Spanish/English bilingual: A case report. Clinical Linguistics and Phonetics, 25, 23–36.

738 A. S. Lee et al. Bakhtiar, M., Seifpanahi, S., Ansari, H., Ghanadzade, M., & Packman, A. (2010). Investigation of the reliability of the SSI-3 for preschool Persian-speaking children who stutter. Journal of Fluency Disorders, 35, 87–91. Caesar, L. G., & Kohler, P. D. (2007). The state of school-based bilingual assessment: Actual practice versus recommended guidelines. Language, Speech & Hearing Services in Schools, 38, 190–200. Chiam, R. (2013). Speech motor control in English-Mandarin bilinguals who stutter. Masters dissertation, University of Canterbury. Einarsdottir, J., & Ingham, R. J. (2009). Does language influence the accuracy of judgments of stuttering in children? Journal of Speech, Language, and Hearing Research, 52, 766–779. Fairbanks, G. (1960). Voice and articulation Drillbook. 2nd ed. New York: Harper & Row. Howell, P. (2004). Assessment of some contemporary theories of stuttering that apply to spontaneous speech. Contemporary Issues in Communication Science and Disorders, 31, 123–140. Howell, P., Au-Yeung, J., Yaruss, S., & Eldridge, K. (2006). Phonological difficulty and stuttering in English. Clinical Linguistics & Phonetics, 20, 703–716. Howell, P., & Au-Yeung, J. (2007). Phonetic complexity and stuttering in Spanish. Clinical Linguistics & Phonetics, 21, 111–127. Howell, P., Ruffle, L., Fernandez-Zuniga, A., Gutierrez, A., Fernandez, A. H., O’Brien, M. L., Tarasco, M., VallejoGomez, I., & Au-Yeung, J. (2004). Comparison of exchange patterns of stuttering in Spanish and English monolingual speakers and a bilingual Spanish-English speaker. In A. Packman, A. Meltzer, & H. F. M. Peters (Eds.), Proceedings of the Fourth World Congress on Fluency Disorders, Montreal, Canada, August 11th–15th; 2003 (pp. 415–422). Nijmegen University Press: Nijmegen. Hubbard, C. P. (1998). Stuttering, stressed syllables, and word onsets. Journal of Speech, Language, and Hearing Research, 41, 802–808. Kohnert, K. (2007). Language disorders in bilingual children and adults. San Diego, CA: Plural. Kohnert, K., & Medina, A. (2009). Bilingual children and communication disorders: A 30-year research retrospective. Seminars in Speech and Language, 30, 219–233. Lewis, M. P., Simons, G. F., & Fennig, C. D. (Eds.). (2013). Ethnologue: Languages of the World, 17th ed. Dallas, TX: SIL International. Retrieved February 17, 2014, from: http://www.ethnologue.com. Lim, V. P. C., Lincoln, M., Chan, Y. H., & Onslow, M. (2008). Stuttering in English-Mandarin bilingual speakers: The influence of language dominance on stuttering severity. Journal of Speech, Language, and Hearing Research, 51, 1522–1537. Owens Jr. R. E. (2005). Language development: An introduction. 6th ed. New York: Pearson. Perkins, W. H., Kent, R. D., & Curlee, R. F. (1991). A theory of neuropsycholinguistic function in stuttering. Journal of Speech and Hearing Research, 34, 734–752. Riley, G. D. (1972). A stuttering severity instrument for children and adults. Journal of Speech and Hearing Disorders, 37, 314–322. Riley, G. D. (1994). Stuttering severity instrument for children and adults, 3rd ed. (SSI-3). Austin, TX: Pro-Ed. Riley, G. D. (2009). Stuttering severity instrument for children and adults, 4th ed. (SSI-4). Austin, TX: Pro-Ed. Roberts, P. M. (2002). Disfluency patterns in four bilingual adults who stutter. Journal of Speech Language Pathology and Audiology, 26, 5–19. Roberts, P. M. (2011). Methodology matters. In P. Howell & J. Van Borsel (Eds.), Multilingual aspects of fluency disorders (pp. 353–369). Bristol, England: Multilingual Matters. Scha¨fer, M., & Robb, M. (2012). Stuttering characteristics of German-English bilingual speakers. Clinical Linguistics & Phonetics, 26, 597–612. Shenker, R. C., Conte, A., Gingras, A., Courcey, A., & Polomeno, L. (1998). The impact of bilingualism on developing fluency in a preschool child. In Second World Congress on Fluency Disorders Proceedings (pp. 200–204). San Francisco. Silverman, S. W., & Bernstein Ratner, N. (1997). Syntactic complexity, fluency, and accuracy of sentence imitation in adolescents. Journal of Speech, Language, and Hearing Research, 40, 95–106. Van Borsel, J. (2011). Review of the relationship between bilingualism and stuttering. In P. Howell & J. Van Borsel (Eds.), Multilingual aspects of fluency disorders. In series: Communication disorders across languages (pp. 247–270). In Mu¨ller & Ball, series (Eds.). Bristol, England: Multilingual Matters. Van Borsel, J., & Britto Pereira, M. M. (2005). Assessment of stuttering in a familiar versus an unfamiliar language. Journal of Fluency Disorders, 30, 109–124. Van Borsel, J., Leahy, M. M., & Britto Pereira, M. (2008). Judging stuttering in an unfamiliar language: The importance of closeness to the native language. Clinical Linguistics and Phonetics, 22, 59–67. Williams, C. J., & McLeod, S. (2012). Speech-language pathologists’ assessment and intervention practices with multilingual children. International Journal of Speech-Language Pathology, 14, 292–305.

Appendix 1: Stuttering Judgement Form

Bilingual stuttering assessment 739

740 A. S. Lee et al.

Copyright of Clinical Linguistics & Phonetics is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.