Severity of anomia, severity rating by people with aphasia and experts, using the Dutch Naming Test

Abstract

Background: Anomia is one of the most frequent deficits in aphasia and is detected with picture naming tests like the Dutch Naming Test (DNT). Although determining severity of anomia is important to have a baseline for therapy and measure progress, severity scores are not yet part of the DNT. It is unclear how anomia, as measured on the DNT, relates to severity of anomia in spontaneous speech and the severity rating of people with aphasia (PWA) and speech language therapists (SLTs). Aim: To determine the level of agreement between severity ratings of Dutch PWA, SLTs and provisional severity scores on the DNT in the rating of severity of anomia, and to produce severity scores for the DNT. Method: A cross-sectional, multicentred study was conducted in 114 PWA in the rehabilitation or chronic phase. SLTs and PWA rated the severity of anomia based on semi-spontaneous speech and the DNT was conducted. Correlations and interrater reliability were determined. Linear regression was applied to calculate severity scores for the DNT based on the cumulative severity scores of PWA, SLTs and provisional severity scores of the DNT. Results: There is a moderate agreement between PWA and SLTs (ICC 0.58) on severity of anomia. Interrater reliability between SLTs and researcher is almost perfect (ICC 0.88). Severity scores for the DNT were calculated by combining the reported severity ratings and the scores on the DNT. Conclusion and recommendations: PWA have a different perspective than SLTs on the severity of anomia. Anomia in spontaneous speech correlates to the scores on the DNT. The severity scores for the DNT can be introduced in SLT practices.