A comparison of the BAT and BDAE-SF batteries in determining the linguistic ability in Greek-speaking patients with Broca's aphasia

Abstract

The aim of this study is to test the validity and reliability of the Bilingual Aphasia Test as a measure of language impairment in a Greek-speaking Broca's aphasic population and to investigate relationships with the same aphasic group's performance on the Greek version of the short form of the Boston Diagnostic Aphasia Examination battery, mainly focusing on a series of subtests which are shared by the two batteries, yet occasionally differ in content. Correlation analyses showed that the two instruments yielded highly comparable results with respect to the measurement of reading and listening comprehension, as well as in the performance-based measurement of the automated sequence capacity of the patients. Nevertheless, the Bilingual Aphasia Test, as a more extensive battery, proved to be more sensitive and objective in characterizing the patients' language abilities in a number of individual language functions, including commands, sentence repetition, naming, verbal fluency and syntactic comprehension.

• aphasia testing
• BAT
• BDAE-SF
• Greek
• Broca's aphasia
• correlation data

Acknowledgements

We would like to thank all the patients who participated in this study, as well as the patients' relatives for their precious help. We are also grateful to neurologist Dr. Tasos Papapostolou for his help with the patients' neurological diagnosis. The authors report no declarations of interest and no sources of financial support for this study. The data sets used in this article are derived from Eleni Peristeri's unpublished Ph.D. thesis (2010) ‘Exploring the Discourse-Syntax and the Lexicon-Syntax Interfaces in Language Pathology: Evidence from Broca's Aphasia’, School of English, Aristotle University of Thessaloniki, Greece, which was supported in part by scholarships from the Propondis Private Foundation and the Research Committee of the Aristotle University of Thessaloniki, Greece.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

Notes

1. Besides the fact that aphasia severity levels on the two batteries are derived from different bases, the BAT's overall mean score representing each patient's extent and type of speech and language impairment derives from a number of extra subtests not included in the BDAE-SF, namely, pointing, syntactic comprehension, synonyms, antonyms, morphology, sentence construction, arithmetic, semantic opposites and metalinguistic abilities. Crucially, the syntactic comprehension section takes up a large proportion of the BAT battery which would probably significantly affect the correlation between the aphasia severity levels generated by the two measures, especially if one takes into account that all the patients recruited for this study were classified into the Broca's aphasia type. Perhaps for other aphasia types especially the fluent ones, this may not affect the scoring of aphasia severity levels, but certainly syntactic comprehension seems to be a crucial factor for assessing non-fluent aphasia types (Peristeri, 2007).

2. Most of the aphasic patients' writing performance was so severely damaged as to be all but unintelligible, so we could not attempt to include that particular section from the two tests.

3. The reader is reminded that we preferred to use ‘word finding relative to speech fluency’ on the BDAE-SF as an index (among others) of the patients' verbal fluency, rather than as a measure of their word naming capacities. The reason for that is our assumption that word finding difficulty in running speech (as in story description or spontaneous speech) may be attributed to factors other than insufficient access to stored word representations, such as syntactic structure complexity which is assumed to cause the greatest difficulty to Broca's aphasics.

4. In fact, to assess whether the patient's syntactic component is intact or not, the BDAE-SF only focuses on spoken output and more specifically on the variety of the syntactic constructions and grammatical markers used by the aphasic individual during spontaneous speech or picture description. In any case, the BDAE-SF provides no direct evidence with respect to the patient's syntactic parsing decisions.