Axis V is for reporting the clinician's judgment of the individual's overall level of functioning. This information is useful in planning treatment and measuring its impact, and in predicting outcome.

The reporting of overall functioning on Axis V can be done using the Global Assessment of Functioning (GAF) Scale. The GAF Scale may be particularly useful in tracking the clinical progress of individuals in global terms, using a single measure. The GAF Scale is to be rated with respect only to psychological, social, and occupational functioning. The instructions specify, "Do not include impairment in functioning due to physical (or environmental) limitations."

The GAF scale is divided into 10 ranges of functioning. Making a GAF rating involves picking a single value that best reflects the individual's overall level of functioning. The description of each 10-point range in the GAF scale has two components: the first part covers symptom severity, and the second part covers functioning. The GAF rating is within a particular decile if either the symptom severity or the level of functioning falls within the range. For example, the first part of the range 41–50 describes "serious symptoms (e.g., suicidal ideation, severe obsessional rituals, frequent shoplifting)" and the second part includes "any serious impairment in social, occupational, or school functioning (e.g., no friends, unable to keep a job)." It should be noted that in situations where the individual's symptom severity and level of functioning are discordant, the final GAF rating always reflects the worse of the two. For example, the GAF rating for an individual who is a significant danger to self but is otherwise functioning well would be below 20. Similarly, the GAF rating for an individual with minimal psychological symptomatology but significant impairment in functioning (e.g., an individual whose excessive preoccupation with substance use has resulted in loss of job and friends but no other psychopathology) would be 40 or lower.

In most instances, ratings on the GAF Scale should be for the current period (i.e., the level of functioning at the time of the evaluation) because ratings of current functioning will generally reflect the need for treatment or care. In order to account for day-to-day variability in functioning, the GAF rating for the "current period" is sometimes operationalized as the lowest level of functioning for the past week. In some settings, it may be useful to note the GAF Scale rating both at time of admission and at time of discharge. The GAF Scale may also be rated for other time periods (e.g., the highest level of functioning for at least a few months during the past year). The GAF Scale is reported on Axis V as follows: "GAF = ," followed by the GAF rating from 0 to 100, followed by the time period reflected by the rating in parentheses—for example, "(current),""(highest level in past year),""(at discharge)." (See examples in Examples of How to Record Results of a DSM-IV Multiaxial Evaluation.)

In order to ensure that no elements of the GAF scale are overlooked when a GAF rating is being made, the following method for determining a GAF rating may be applied:

	STEP 1: Starting at the top level, evaluate each range by asking "is either the individual's symptom severity OR level of functioning worse than what is indicated in the range description?"
	STEP 2: Keep moving down the scale until the range that best matches the individual's symptom severity OR the level of functioning is reached, whichever is worse.
	STEP 3: Look at the next lower range as a double-check against having stopped prematurely. This range should be too severe on both symptom severity and level of functioning. If it is, the appropriate range has been reached (continue with step 4). If not, go back to step 2 and continue moving down the scale.
	STEP 4: To determine the specific GAF rating within the selected 10-point range, consider whether the individual is functioning at the higher or lower end of the 10-point range. For example, consider an individual who hears voices that do not influence his behavior (e.g., someone with long-standing Schizophrenia who accepts his hallucinations as part of his illness). If the voices occur relatively infrequently (once a week or less), a rating of 39 or 40 might be most appropriate. In contrast, if the individual hears voices almost continuously, a rating of 31 or 32 would be more appropriate.

In some settings, it may be useful to assess social and occupational disability and to track progress in rehabilitation independent of the severity of the psychological symptoms. For this purpose, a proposed Social and Occupational Functioning Assessment Scale (SOFAS) (see Social and Occupational Functioning Assessment Scale [SOFAS]) is included in Appendix B. Two additional proposed scales that may be useful in some settings—the Global Assessment of Relational Functioning (GARF) Scale (see Global Assessment of Relational Functioning (GARF) Scale) and the Defensive Functioning Scale (see Defensive Functioning Scale)—are also included in Appendix B.