Participants are rated on their symptom severity using the Clinical Global Impression Severity Scale (CGI-S) and the Global Assessment of Functioning (GAF). The Clinical Global Impression scale (CGI) is frequently used in clinical research because of its face validity and practicability. The GAF combines the evaluation of symptoms as well as relational, social, and occupational functioning on a single axis. The scale runs from 1 to 100 and is divided into 10 equal parts providing defining characteristics, both symptoms and functioning, for each 10-point interval. A low rating reflects worse symptoms and a poorer level of functioning, whereas a high rating reflects less symptoms and a better level of functioning.
