Treatment fidelity in eating disorders and psychological research: Current status and future directions

Objective: The evaluation and use of treatment fidelity procedures are rare in the development and implementation of psychological interventions. This article aims to review the construct of treatment fidelity, highlight limitations to currently available measures, and introduce a conceptual framework for studying and adapting fidelity measures in clinical research and practice using eating disorders as an example. Method: As treatment fidelity assesses whether an intervention was delivered as intended, we operationalized this construct as: (a) treatment adherence, (b) therapist competence, and (c) treatment differentiation. Results: There is a significant gap in the literature assessing and documenting treatment fidelity. Available studies indicate that existing adherence measures can be time consuming, costly, and are not widely used in the field. Furthermore, therapist competence is a complex and context-dependent construct that is challenging to measure. Finally, treatment differentiation is often inferred by ensuring adherence. Discussion: The development of simplified formal tests of treatment fidelity would help draw conclusions about treatment efficacy and improve the dissemination and implementation of interventions to promote optimal clinical outcomes.