Can anyone be Hypnotized?
Yes, if they want to.
Is Hypnotherapy Effective?
Hypnosis has a better success rate than any other type of therapy.
In 1970 a groundbreaking meta-analysis of hypnosis research studies was conducted by Alfred A. Barrios, clinical psychologist, which led to mainstream acceptance of hypnosis as an extremely effective form of therapy.
Barrios compared 1,018 studies and articles on hypnosis, 899 articles on psychoanalytic therapy and 355 on behavioral therapy. In particular he noted the overall lasting success rates of the different therapies.
He found that hypnotherapy had a 93% success rate after only 6 sessions compared to only a 72% success rate with behavioral therapy (after 22 sessions on average), and only 38% success rate with psychotherapy (after an average of 600 sessions).
This led him to conclude that for changing habits, thought patterns, and actual behavior, hypnosis was not only the most effective method, but it also required less time / sessions than any other type of therapy.