Final answer:
The therapist could have used self-reporting, behavioral observations, physiological measurements, or verbal affirmations to determine a decline in the patient's belief about being followed by a witch.
Step-by-step explanation:
The therapist determined that the patient's belief that a witch was following him actually declined potentially through various methods, such as self-reporting by the patient, which means the patient explicitly expressed a reduction in this belief. Therapists may also rely on behavioral observations, documenting changes in the patient's actions that might indicate a decrease in the belief, such as showing less fear or avoidance behavior related to the belief about the witch. Other methods, like physiological measurements (monitoring heart rate, perspiration, etc.), could provide objective data on the patient's stress or anxiety levels linked to the belief. Finally, therapists might consider verbal affirmations from the patient; given the context, verbal affirmations are essentially a form of self-reporting where the patient verbally confirms changes in their belief or behavior.