The evidence base for the assessment and management of speech and language disorders, related to bilingualism or multilingualism

Hanneke Kalf (h.kalf@pmd.umcn.nl)

Radboud University Medical Centre

Department of Allied Health

Speech and language therapy

Nijmegen, The Netherlands

www.umcn.nl

Currently ‘evidence-based practice’ is a recognized aspect of health care and health sciences. It implies that whenever there is scientific evidence for the clinical value of an assessment or treatment, it should be used to help making these right decisions during interventions (Sackett et al., 2001; Guyatt & Rennie, 2002). This is also known as quantitative research, meaning that the outcome is given in numbers or percentages of people that benefit or are at risk. In the relatively new field of multilingualism in speech and language therapy, the question rises: what is the evidence base and how to find and use it? Is there any evidence concerning validity of specific assessments or efficacy of specific treatment? Or is the evidence concentrated around questions about features in the field of linguistics, phonology, acquired disorders etc.?

The scope of the Journal of Multilingual Communication Disorders (published since 2003), for example is formulated: “In recent years, the emphasis on multilingual and multicultural issues in speech-language pathology has increased markedly. However, there is still a dearth of studies that can serve as the basis of best practice with populations whose languages do not form part of the typical research mainstream.” (http://www.tandf.co.uk/journals/titles/14769670.html).

This paper will review the following aspects for this subject: useful search terms, most used journals, a comparison of databases and the kind of evidence currently available.

Which search terms and which databases are most useful?

The following searches have been done in June 2006, using PubMed (MedLine, biomedical database) Cinahl (database for nursing and allied health sciences) and PsycInfo (database for behavioural sciences). The same search terms (subject headings from thesaurus) were used for all databases. The first search was for ‘Multilingualism’, a term that includes ‘bilingualism’. The second search was to find studies indexed with terms ‘Language development’ or ‘Language disorders’ or ‘Speech disorders’. The third step was combining these strategies. Using the three databases together, this revealed a total number studies of 335. The results per database are shown in Table 1.

Database	MedLine (via PubMed)	Cinahl	PsycInfo
Access	www.pubmed.gov	www.cinahl.com	www.psycinfo.com
Results	180 studies: 23 reviews, 8 clinical trials	140 studies: 13 reviews, 2 clinical trials	54 studies: 13 reviews, 0 clinical trials

Table 1. Results form the search strategie (see text) in three databases.

MedLine, although it is a biomedical database, still seems to reveal the most relevant studies according to the chosen search terms.

Which journals publish about bilingual/multilingual issues and SLT?

Studies concerning aspects of multilingualism can be found in many journals that are internationally available. Table 2 shows the journals that were found frequently in the searches described above, including the website of the publisher that allows to browse the journal contents (see also: www.cplol.org).

PubMed is free accessible on the internet, but does it have enough journals indexed concerning studies on multilingualism and speech and language therapy, compared to PsycInfo or Cinahl, both databases only accessible via subscription? Interestingly, the most specific journal in this field, the Journal of Multilingual Communication Disorders, is only indexed in Cinahl, thus will be missed when searching in PubMed.

Journal name	Indexed in			Website
Journal name	MedLine	Cinahl	PsycInfo	Website
Acta Pediatrica	M	-	-	http://www.tandf.co.uk/journals
American Journal of Speech Language Pathology	M	C	P	http://www.asha.org/about/publications
Brain and Language	M	C	P	http://www.sciencedirect.com
Child Language Teaching and Therapy	-	C	P	http://www.arnoldpublishers.com
Clinical Linguistics and Phonetics	M	C	P	http://www.tandf.co.uk/journals
Dyslexia	M	-	P	http://www3.interscience.wiley.com
Folia Phoniatrica et Logopaedica	M	C	P	http://content.karger.com
International Journal of Language and Communication Disorders	M	C	P	http://www.tandf.co.uk/journals
Journal of Child Language	M	C	P	http://journals.cambridge.org
Journal of Communication Disorders	M	C	P	http://www.sciencedirect.com
Journal of Multilingual Communication Disorders	-	C	-	http://www.tandf.co.uk/journals
Journal of Speech Language and Hearing Research	M	-	P	http://www.asha.org/about/publications
Language, Speech and Hearing Services in Schools	M	C	-	http://www.asha.org/about/publications
Seminars in Speech and Language	M	C	P	http://www.thieme-connect.com
Studies in Second Language Acquisition	-	-	P	http://journals.cambridge.org
Topics in Language Disorders	-	C	P	http://www.topicsinlanguagedisorders.com

Table 2. Overview of relevant journals concerning multiligualism and speech pathology and the databases they are indexed in.

What is the evidence?

There is quite an amount of evidence around phonological development, dyslexia in bilingual children, acquired speech and language disorders in bilingual adults or communicative consequences of bilingualism and multilingualism. However, controlled studies evaluating specific interventions or psychometric studies evaluating specific assessment tools are very limited. The question is whether assessments and interventions need to be very specific in this field or whether new outcome instruments and therapies are currently being developed and scientific evaluation is on its way.

Finally, the way to exchange scientific and clinical experience in itself can be a multilingual problem. In this review only American databases are used, which index journals of many countries, but the majority is in English. The reason for this language bias by the author is simply because these databases are widely used and easy within reach in a Dutch university library.

References

Guyatt G, Rennie D. Users’ guides to the medical literature. AMA Press. Chicago, 2002.

Sackett DL, Strauss SE, Richardson WS, Rosenberg W, Haynes RB Evidence-based Medicine. How to practice and teach EBM. Edinburgh: Churchill Livingstone, 20001

Journal name

References