The Global Assessment of Functioning is a clinical diagnostic scale used to rate the subject's level of function in three categories: psychological, social and occupational. Either the symptom severity (anxiety, insomnia) or the level of functioning (can't hold job, neglects personal hygiene) is rated (whichever is lower or "worse").
The scale runs from 100 (superior functioning) to 1 (persistent risk of injury to self or others, suicidal, inability to perform personal care/hygiene).
I'll be honest - not every assessment which I discuss during A to Z can be helpful in crafting characters. (I'm doing my best.) The only use I've found for this one is in grouping common functional levels/symptoms for characters who may be suffering from some sort of psychological or mental impairment. The scale would provide a starting point to describe observable behaviors. For instance, on the 31-40 region of the scale:
Some impairment in reality testing or communication (e.g., speech is at times illogical, obscure, or irrelevant) or major impairment in several areas, such as work or school, family relations, judgment, thinking, or mood (e.g., depressed adult avoids friends, neglects family, and is unable to work; child frequently beats up younger children, is defiant at home, and is failing at school).
Find the full GAF scale here.
Adjectives for the day: galliard, gibbous, glabrous, glutinous, goluptious, gormless, graveolent