Final answer:
The clinician primarily determines whether fear or anxiety is excessive as per the DSM-5. This determination is informed by the clinician's expertise and assessment of the patient's symptoms against DSM-5 criteria.
Step-by-step explanation:
According to the DSM-5, the clinician primarily determines whether fear or anxiety is excessive. The Diagnostic and Statistical Manual of Mental Disorders (DSM-5) is used by clinicians to diagnose and categorize mental health conditions. The role of the clinician is to evaluate the symptoms presented by the patient in the context of the criteria set forth in the DSM-5. This evaluation includes determining if the fear or anxiety experienced by a patient is disproportionate to the actual threat or danger posed by the situation, thereby classifying it as excessive. This judgement is informed by the clinician's expertise, the patient's self-report, observed behavior, and possibly input from others who know the patient well; nevertheless, the responsibility to make this determination lies with the clinician.