Identifying language impairment in bilingual children in France and in Germany.

BACKGROUND: The detection of specific language impairment (SLI) in children growing up bilingually presents particular challenges for clinicians. Non-word repetition (NWR) and sentence repetition (SR) tasks have proven to be the most accurate diagnostic tools for monolingual populations, raising the question of the extent of their usefulness in different bilingual populations. AIMS: To determine the diagnostic accuracy of NWR and SR tasks that incorporate phonological/syntactic complexity as discussed in recent linguistic theory. The tasks were developed as part of the Language Impairment Testing in Multilingual Settings (LITMUS) toolkit, in two different national settings, France and Germany, and investigated children with three different home languages: Arabic, Portuguese and Turkish. METHODS & PROCEDURES: NWR and SR tasks developed in parallel were administered to 151 bilingual children, aged 5;6-8;11, in France and in Germany, to 64 children in speech-language therapy (SLT) and to 87 children not in SLT, whose first language (L1) was Arabic, Portuguese or Turkish. Children were also administered standardized language tests in each of their languages to determine likely clinical status (typical development (TD) or SLI), and parents responded to a questionnaire including questions about early and current language use (bilingualism factors) and early language development (risk factors for SLI). Monolingual controls included 47 TD children and 29 children with SLI. Results were subjected to inter-group comparisons, to diagnostic accuracy calculation, and to correlation and multiple regression analyses. OUTCOMES & RESULTS: In accordance with previous studies, NWR and SR identified SLI in the monolingual children, yielding good to excellent diagnostic accuracy. Diagnostic accuracy in bilingual children was fair to good, generally distinguishing children likely to have SLI from children likely to have TD. Accuracy was necessarily linked to the determination of clinical status, which was based on standardized assessment in each of the child's languages. Positive early development, a composite risk factor for SLI, and not variables related to language exposure and use, generally emerged as the strongest predictor of performance on the two tasks, constituting additional, independent support for the efficacy of NWR and SR in identifying impairment in bilingual children. CONCLUSIONS & IMPLICATIONS: NWR and SR tasks informed by linguistic theory are appropriate for use as part of the diagnostic process for identifying language impairment in bilingual children for whom the language of assessment is different from the home language, in diverse sociolinguistic contexts.

Development and evaluation of a linguistically and audiologically controlled sentence intelligibility test.

To allow for a systematic variation of linguistic complexity of sentences while acoustically controlling for intelligibility of sentence fragments, a German corpus, Oldenburg linguistically and audiologically controlled sentences (OLACS), was designed, implemented, and evaluated. Sentences were controlled for plausibility with a questionnaire survey. Verification of the speech material was performed in three listening conditions (quiet, stationary, and fluctuating noise) by collecting speech reception thresholds (SRTs) and response latencies as well as individual cognitive measures for 20 young listeners with normal hearing. Consistent differences in response latencies across sentence types verified the effect of linguistic complexity on processing speed. The addition of noise decreased response latencies, giving evidence for different response strategies for measurements in noise. Linguistic complexity had a significant effect on SRT. In fluctuating noise, this effect was more pronounced, indicating that fluctuating noise correlates with stronger cognitive contributions. SRTs in quiet correlated with hearing thresholds, whereas cognitive measures explained up to 40% of the variance in SRTs in noise. In conclusion, OLACS appears to be a suitable tool for assessing the interaction between aspects of speech understanding (including cognitive processing) and speech intelligibility in German.

How does linguistic complexity influence intelligibility in a German audiometric sentence intelligibility test?

OBJECTIVE: We investigated if linguistic complexity contributes to the variation of the speech reception threshold in noise (SRTN) and thus should be employed as an additional design criterion in sentence tests used for audiometry. DESIGN: Three test lists were established with sentences from the Göttingen sentence test ( Kollmeier & Wesselkamp, 1997 ). One list contained linguistically simple sentences, the other two lists contained sentences with two types of linguistic complexity. For each listener the SRTN was determined for each list. STUDY SAMPLE: Younger and older listeners with normal hearing and older listeners with hearing impairment were tested. RESULTS: Younger listeners with normal hearing showed significantly worse SRTNs on the complex lists than on the simple list. This difference could not be found for either of the older groups. CONCLUSIONS: The effect of linguistic complexity on speech recognition seems to depend on age and/or hearing status. Hence, pending further research, linguistic complexity seems less relevant as a sentence test design criterion for clinical-audiological purposes, but we argue that a test with larger variation in linguistic complexity across sentences might show a relation between linguistic complexity and speech recognition even in a clinical population.