Aphasia has a large impact on the quality of life and adds significantly to the costs of stroke care. Early recognition of aphasia in stroke patients is important for prognostication and well-timed treatment planning. We aimed to identify available screening tests for differentiating between aphasic and non-aphasic stroke patients, and to evaluate test accuracy, reliability, and feasibility. We searched PubMed, EMbase, Web of Science, and PsycINFO for published studies on screening tests aimed at assessing aphasia in stroke patients. The reference lists of the selected articles were scanned, and several experts were contacted to detect additional references. Of each screening test, we estimated the sensitivity, specificity, likelihood ratio of a positive test, likelihood ratio of a negative test, and diagnostic odds ratio (DOR), and rated the degree of bias of the validation method. We included ten studies evaluating eight screening tests. There was a large variation across studies regarding sample size, patient characteristics, and reference tests used for validation. Many papers failed to report on the consecutiveness of patient inclusion, time between aphasia onset and administration of the screening test, and blinding. Of the three studies that were rated as having an intermediate or low risk of bias, the DOR was highest for the Language Screening Test and ScreeLing. Several screening tools for aphasia in stroke are available, but many tests have not been verified properly. Methodologically sound validation studies of aphasia screening tests are needed to determine their usefulness in clinical practice.

Standard nonlinguistic cognitive examination is recommended in aphasic stroke patients. Nonlinguistic cognitive impairments are common and associated with poor functional outcome and depression, especially in patients with persisting aphasia.

The outcome of aphasia at 1 year after stroke can be predicted in the first week by the phonology score, the Barthel Index score, age, educational level and stroke subtype, with phonology being the strongest predictor.

Semantics, phonology, and syntax are essential elements of aphasia diagnosis and treatment. Until now, these linguistic components have not been specifically addressed in follow-up studies of aphasia recovery after stroke. The aim of this observational prospective follow-up study was to investigate semantic, phonological, and syntactic recovery in aphasic stroke patients. In addition, we investigated the recovery of verbal communication and of aphasia severity. We assessed 147 aphasic patients at 1, 2, and 6 weeks, 3 and 6 months, and 1 year after stroke with the ScreeLing, a screening test for detecting deficits on the three main linguistic components, the aphasia severity rating scale (ASRS), a measure of verbal communication, and the Token test, a measure of aphasia severity. We investigated the differences in scores between the six time points with mixed models. Semantics and syntax improved up to 6 weeks (p < 0.001) after stroke, and phonology up to 3 months (p ≤ 0.001). ASRS improved up to 6 months (p < 0.05) and the Token test up to 3 months (p < 0.001). We conclude that in aphasia after stroke, various linguistic components have a different recovery pattern, with phonology showing the longest period of recovery that paralleled aphasia severity, as measured with the Token test. The improvement of verbal communication continues after the stabilization of the recovery of the linguistic components.