Abstract
The precise measurement of treatment fidelity (quantity and quality in the delivery of treatment strategies in an intervention) is essential for intervention development, evaluation, and implementation. Various informants are used in fidelity assessment (e.g., observers, practitioners [clinicians, teachers], clients), but these informants often do not agree on ratings. This scoping review aims to ascertain the state of science around multi-informant assessment of treatment fidelity.
A literature search of articles published through December 2021 identified 673 articles. Screening reduced the number of articles to 44, and the final study set included 35 articles.
There was substantial variability across studies regarding study design, how fidelity was operationalized, and how reliability was defined and assessed. Most studies evaluated the agreement between independent observers and practitioner-report, though several other informant pairs were assessed. Overall, findings suggest that concordance across fidelity informants was low to moderate, with a few key exceptions.
It is difficult to draw clear conclusions about the degree to which single versus multiple informant assessment is needed to produce an accurate and complete picture of treatment fidelity. The field needs to take steps to determine how to leverage multi-informant assessment to accurately assess treatment fidelity.
