Acquisition and Generalization Responses in Aphasia Naming Treatment: A Meta-Analysis of Semantic Feature Analysis Outcomes.

Abstract

Purpose This meta-analysis synthesizes results from published studies that used semantic feature analysis (SFA) treatment to improve naming for people with aphasia. It examines how both person- and treatment-related variables affected the likelihood of correct naming responses in individual probe sessions for both acquisition (treated) and generalization (untreated) stimuli. Method The meta-analysis compiled data from 12 studies analyzing a total of 35 participants with aphasia. It used mixed-effects models as a novel statistical tool to examine the effects of 2 sets of variables on naming performance: treatment-related variables, including treatment phase (baseline vs. treatment), dosage (number of treatment sessions), and stimulus type (treated vs. untreated, semantically related vs. unrelated items), and person-specific variables, including degree of language impairment and demographic variables (age, time poststroke). Results Results of the meta-analysis revealed that SFA intervention promoted increased naming accuracy during naming probes when comparing baseline and treatment phases. In addition, increased dosages of SFA were associated with increased naming accuracy, and treatment-related gains were larger for acquisition (treated) than generalization (untreated) stimuli, likewise for related versus unrelated generalization stimuli. Furthermore, a subset of person-specific variables was predictive of SFA-related gains: Language impairment variables were related to treatment-related changes in naming performance, but demographic variables were not. Conclusion These results provide group-level evidence for the efficacy of SFA as well as preliminary estimates of how much naming performance benefit is engendered by varying dosages of SFA. The results also provide promising and previously unobserved evidence of potential person-level predictors of SFA treatment response.