Post-stroke aphasia assessment in Arabic-speaking populations: A critical review of validated tools, structural barriers, and the diglossic validity problem.

Arabic is spoken by more than 400 million people across a region experiencing a substantial increase in stroke burden. Yet, no comprehensively validated aphasia assessment battery exists that provides dialect-stratified norms across major Arabic-speaking communities. This critical narrative review evaluates Arabic aphasia assessment against explicit psychometric and linguistic criteria, identifying peer-reviewed instruments and synthesizing the methodological progress they represent, alongside two structural questions that are only partially resolved by existing instruments. The first is the diglossic register question: Modern Standard Arabic functions as a learned register whose distance from each speaker's vernacular varies with education, and how this distance contributes to assessment score variance has not been quantified in within-subject clinical samples. The second is the nonconcatenative morphology question: Arabic root-and-pattern morphological operations, not specifically assessed by current aphasia batteries, leave possible morphology-specific vulnerability insufficiently tested. Recent dialect-specific instruments, including the Moroccan Arabic Bedside WAB-R, the Cairene Egyptian Arabic WAB-R, the Egyptian Arabic Comprehensive Aphasia Test, the Short Aphasia Test for Gulf Arabic, and the Arabic Discourse Assessment Tool, represent substantive progress and a necessary foundation. Building on it requires dialect-specific psycholinguistic databases, measurement-equivalence reporting as a publication standard, education- and literacy-stratified normative collection, and a within-subject crossover study quantifying the register-distance effect. Improving Arabic aphasia assessment is essential: lesion-symptom mapping in Arabic-speaking populations depends on instruments validated for the linguistic profile they assess.