Okay.
Rapport, the capacity to actually engage with an individual, is probably the most critical component for maintaining anyone in a treatment protocol. It doesn't matter what it is, the person has to feel like they have a relationship with that person. Whether you're offering CBT or whether you're offering any of the other protocols that could be available, it doesn't matter; you have to be able to build a relationship. The person has to believe you have a relationship. For the most part, as long as that relationship is supportive and maintained, I think you'll see good retention. I think a failure of retention occurs when you have a failure of that relationship.
Broadly speaking, I'd say it's about that relationship. Most success and failure of therapy, I believe, does still require that relationship. It's just what you're doing after you have that relationship that I think differentiates between really effective treatments and treatments that could be more effective.