A Systematically Conducted Scoping Review of the Evidence and Fidelity of Treatments for Verb and Sentence Deficits in Aphasia: Sentence Treatments

Purpose: This review article synthesizes and evaluates the evidence for sentence production treatments in aphasia, systematically charting impairment-based and functional communication outcomes. It reports (a) the level of evidence and fidelity of sentence treatments; (b) the impact of treatment on production of trained and untrained verbs and sentences, functional communication, and discourse; and (c) the potential active ingredients of treatment. Method: The search included studies from January 1980 to June 2019. The level of evidence of each study was documented, as was fidelity in terms of treatment delivery, enactment, and receipt. Studies were also categorized according to treatment methods used. Results: Thirty-three studies were accepted into the review and predominantly constituted Level 4 evidence (e.g., case control studies and case series). Thirty studies (90%) described treatment in sufficient detail to allow replication, but dosage was poorly reported, and fidelity of treatment was rarely assessed. The most commonly reported treatment techniques were mapping (10 studies: 30%), predicate argument structure treatment (six studies: 18%), and verb network strengthening treatment (five studies: 15%). Production of trained sentences improved for 83% of participants, and improvements generalized to untrained sentences for 59% of participants. Functional communication was rarely assessed, but discourse production improved for 70% of participants. Conclusions: The evidence for sentence treatments is predominantly generated from Level 4 studies. Treatments were effective for the majority of participants regarding trained sentence and discourse production. However, there is inconsistent use of statistical analysis to verify improvements, and diverse outcome measures are used, which makes interpretation of the evidence difficult. The quality of sentence treatment research would be improved by agreeing a core set of outcome measures and extended by ascertaining the views of participants on sentence treatments.