Language assessment in bi/multilingual aphasia: a scoping review of trends and challenges

Background The assessment of bilingual and multilingual aphasia is hampered by a lack of clinical resources for assessment and by inconsistent definitions of bi/multilingualism. Improving language assessment procedures for bi/multilingual people with aphasia (PWA) requires an understanding of how researchers and clinicians define and measure bi/multilingualism, along with the tools and processes they use for comprehensive assessment.Aims This scoping review aimed to map the current state of bi/multilingual aphasia assessment by exploring how bi/multilingualism is defined and operationalised in aphasia language assessment and identifying the tools and processes used to evaluate the language abilities of bi/multilingual PWA.Methods & Procedures Using Arksey & O’Malley’s framework for scoping reviews, a systematic literature search was conducted. Six electronic databases were searched using a combination of terms related to “bilingual”, “multilingual”, “aphasia”, and “assessment”. Key variables were extracted from studies that met the inclusion criteria for analysis.Outcomes & Results A total of 135 studies were included in the final analysis, including both research-focused and clinically-oriented studies. Of these, 31 studies defined bi/multilingualism, though definitions varied widely. In 90 studies, bi/multilingualism was measured to determine the pre- and/or post-morbid language profiles of PWA across all their languages, most often through self-report. Ninety-seven diagnostic and supplemental assessments covering over 50 languages were identified. Only five studies reported involving certified interpreters to support language assessment, while most studies evaluated bi/multilingual participants in all the languages they spoke. All studies tended to supplement standardised test batteries with non-standardised tasks, aiming to address gaps in language pair coverage and accommodate practical limitations.Conclusions This review identified limitations in existing assessment practices for bi/multilingual PWA. Particularly, the infrequent and inconsistent definition of bi/multilingualism poses a challenge to the quality and comparability of assessment procedures for this population. Although numerous language assessment tools exist, the frequent use of certain tools highlights the limited availability of validated alternatives for many linguistic communities. Inconsistent reporting about assessors’ language competencies or interpreter involvement raises additional questions about whether appropriate linguistic support is available to facilitate assessment. Findings from this review will help to inform the development of responsive assessment practices that capture the language profiles of bi/multilingual PWA and underscore the need for consistent assessment guidelines for this population.