What is fidelity?
Fidelity refers to the degree of implementation of an evidence-based practice (EBP). A fidelity scale measures fidelity. Such scales have been developed for each of the six EBPs included in the Implementing EBP Project (assertive community treatment, supported employment, integrated treatment for dual disorders, illness management, family psychoeducation, and medication guidelines). Each scale assesses approximately 15 to 30 critical ingredients of the EBP, based on its underlying principles and methods. The scale items provide concrete indications that the practice is being implemented as intended. For example, one item on the Supported Employment Fidelity Scale concerns rapid job search. This item is rated as fully implemented if the consumers in a program average one month or less between admission to the supported employment program and their first job interview. Why measure fidelity? Several assumptions underlie the use of fidelity scales. First, a fidelity scale should adequately
