Overview
Fidelity is the quality of being faithful or loyal to something, sometimes with an implication of accurately reflecting something else. For instance, when examining the treatment fidelity of a therapeutic intervention, we might look at how closely the therapist follows a manualized outline to implement the intervention. Every therapist is only human after all, and each client has their own unique needs and experiences, so no intervention can be implemented with complete fidelity to theoretical ideals.