Intervention fidelity in physical therapy research and practice

What is it about?

Intervention fidelity is the degree to which interventions, treatments or programmes have been put into practice as intended by their developers. When developing and testing interventions or treatments in physical therapy research, we can only be certain that the outcomes of that testing is accurate if the intervention fidelity is high. In other words, the better the fidelity to the intended intervention, the more we can be sure that the outcomes and effects we are seeing are actually down to that intervention, and not to other extraneous elements. For example, the results of testing may find that a certain treatment is ineffective, but we may subsequently find out that none of the physical therapists delivered the treatment as intended (e.g. they only taught some of the exercises, did not deliver all of the education needed). Therefore, we cannot be sure that the treatment itself is ineffective, as it was not delivered as intended and therefore not accurately tested.

Featured Image

Why is it important?

With adequate fidelity, one can attribute findings confidently to the intervention itself and not to unknown elements omitted from or added to it, enabling a more accurate interpretation of research findings. Furthermore, assessing fidelity of intervention delivery provides more understanding of what has actually been delivered during an intervention, enabling effective and successful interventions to be more accurately replicated and implemented into clinical settings by practitioners. As such, intervention fidelity is hugely relevant both to researchers and clinicians. Moreover, health service resources are directed toward evidence-based practices; however, if the evidence base is questionable due to poor intervention fidelity in evaluation studies, or is poorly reported to inhibit replication in clinical settings, or if clinicians and practitioners deliver evidence-based treatments with poor fidelity, then precious resources in both research and clinical settings are wasted and patients are given false promise.

Perspectives