Whew. You are taking me back to my college days. There have been many behavioral theorists; there is no unified theroy of behaviorism. Ultimately, the theories have revolved around conditioning: learned behavior that is either operantly or classically conditioned. Pavlov's experiments in which he trained dogs to salivate at the sound of a bell that had been temporally paired with meat, is an example of classical conditioning. Using biofeedback devices to learn to increase or decrease your heart rate would be an example of operant conditioning. Perhaps the person best known for operant conditioning is B.F. Skinner. However, there are many others. You really should consult a textbook of psychology for this. Hope this has addressed in part your question. Behavioral interventions in the context of medical care generally means some combination of meditation or relaxation plus cognitive behavior therapy in which people learn to change their cognitions in hopes of reducing symptoms.