Adverse events of cognitive behavioral therapy (CBT) can be used to identify two types depending on whether or not CBT is practiced appropriately. The results of a randomized control trial (RCT) when CBT is performed effectively show that the rate of adverse events is as low as, or lower than, that on using a pill placebo. Many adverse events are associated with a low quality of CBT caused by inappropriate practice due to therapists' lack of knowledge, skills, and experience. In order to achieve effective CBT for RCT, it is considered important to frequently assess the status of patients before and during CBT sessions, utilize the Cognitive Therapy Rating Scale after the session, and conduct supervision based on audio recordings of the session.
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