Replication in Evidence-Based Aphasia Treatments

A critical review was completed to evaluate replication of aphasia treatments that have been vetted and accepted on the American Speech-Language-Hearing Association Practice Portal.

The electronic databases Academic Search Premier, ProQuest Central, CINAHL Complete, and ERIC were searched for relevant articles using treatment names as keywords. Coders compared stimuli, material, design, and statistical analysis to pilot treatment approaches. Each study was coded as direct, conceptual, failed, or no replication.

Eighteen treatment approaches were selected for this review. A total of 188 articles met the inclusion criteria. Results revealed that 14 out of 18 treatment approaches were somehow replicated. Direct replications as the most valuable replication type for affirming previously found results were represented in only 1.5% of all studies (3/188). Failed direct replication were at 2% overall (4/188). Conceptual replications were more common across treatment approaches, but also represented at a low level with 22.8% (43/188). The majority of studies were coded as no replication attempt with 73.4%.

A critical factor in developing an evidence-based practice is the existence of replicated results for treatment. Replication evaluates the reproducibility of an author's or authors' research methodology and resulting outcomes and helps to ensure that observed treatment effects are reproducible. For an evidence-based treatment to be implemented or used in any clinical setting, it must be one that can be replicated. Direct and conceptual replications of aphasia treatment approaches were found to be alarmingly low considering the importance of replication in our field. It is recommended that replication should become more valued and mainstreamed in aphasia research. A replication database that compiles and maintains treatment manuals for replication purposes can increase the accessibility and acceptability of replications for researchers.