Development and validation of the Overall Fidelity Enactment Scale for Complex Interventions (OFES-CI).

The OFES-CI provides a promising novel approach for assessing fidelity enactment in QI and other complex interventions. It demonstrates good reliability against our gold standard assessment approach and addresses the practicality problem in fidelity assessment by virtue of its suitable implementation qualities. Steps for adapting the OFES-CI to other complex interventions are offered.