Aphasia investigators from Australia have published a systematic review of peer-reviewed articles since 2012 that report on randomized controlled trials (RCT) investigating aphasia therapy efficacy. In these articles, the authors focused particularly on participant’s treatment fidelity, which prior to 2012 was addressed in only 14% of such RCT reports. They note that absence of treatment fidelity reporting complicates the interpretation of RCT findings, by compromising ascription of causality to the researchers’ experimental procedures. It is rigorous adherence to prescribed protocols – that is, treatment fidelity – that establishes elements of the prescribed intervention, rather than external factors, as effective causes of interventions’ documented benefits.
To conduct their review, the authors identified 110 candidate articles published between 2012 and 2017, through online databases searches of speechBITE, MEDLINE, and CINAHL. Of these, they culled 42 that met four additional inclusion criteria: (a) the research focused on impairment-based therapeutic interventions for post-stroke aphasia; (b) the research was original, as opposed replication studies, feasibility studies, etc.; (c) the study did not involve surgical or pharmacological interventions; and (d) the article was published in English. The investigators then rated these 42 qualifying articles in the 5 key treatment fidelity areas, using a published Template for Intervention Description and Replication. The key areas broadly – each with two to four subpoints –are: (a) study design; (b) provider training; (c) treatment delivery; (d) treatment receipt; and (e) carryover and generalization by subjects afterwards.
The investigators’ analyses reveal that attention to treatment fidelity has been rising since 2012, but unevenly across the spectrum of concerns. The key area (a) fared best, with 88.1% of articles reporting prospective plans to monitor and report on treatment fidelity. Attention to key implementation areas (b) and (c) fared moderately well: 47.6% of articles reported on (b), provider training; while 50.0% reported it for (c), treatment delivery. The remaining two areas, however, fared poorly. Just 11.9% of articles reported treatment fidelity for (d), receipt of treatment; and only a single article out of 42 (2.4%) reported it for (e) carryover and generalization.
The authors conclude that researchers conducting RCTs of aphasia therapy efficacy have made strides since 2012 in actively tracking and reporting treatment fidelity. However, this attention is not yet evenly allocated across to spectrum of treatment fidelity concerns. Consistent, comprehensive reporting appears to be an achievable goal, but its accomplishment will require additional methodological development, time, and effort. In the interim, service providers will still be relying on the traditional fallbacks, namely, clinical experience and intuition. But only with treatment fidelity data will they be able to identify with confidence precisely when, where, how, and with whom a given therapeutic regimen can be most efficaciously delivered.
For further reading: E. Brogan, N. Ciccone, E. Godecke, 2019. Treatment fidelity in aphasia randomized controlled trials. Aphasiology, 33(7): 759-779. DOI: 10.1080.02687038.2019.1576442