Facilitators' delivery of a psychosocial intervention in a controlled trial for men with prostate cancer and their partners: a process evaluation.

These findings will be useful for further development and evaluation of the intervention. A tentative conceptual framework of factors, related to facilitators, influencing the fidelity of interventions in the context of controlled trials, is offered. This model, which requires further development and testing, will be useful for researchers worldwide who are involved in developing interventions and training facilitators.