Purpose of the Scale

The main objective of the Global Assessment of Functioning Scale (GAF) is to provide a comprehensive evaluation of an individual’s functionality, particularly in cases where the person is experiencing a form of mental disorder, along with the current burden on their psychological well-being.

Scale Analysis

The Global Assessment of Functioning Scale (GAF) was developed by Spitzer et al. in 1976 and was adapted into Greek by Madianos in 1987. Specifically, the holistic functionality of an individual, at a given moment, is positioned along a continuum of mental health–illness. Based on this theory, the creators aimed to simultaneously identify the manifestation of psychopathological conditions and assess the degree to which the individual maintains their activity level.

Scale Scoring

The GAF is divided evenly into ten sections, with scores ranging from 1 to 100:
Scores between 80 and 100: Assigned to individuals who do not present with any mental or physical problems and are socially active with strong interpersonal interaction.
Scores between 31 and 70: Reflect individuals who are seeking professional help for psychological issues.
Scores between 1 and 30: Typically correspond to individuals who are hospitalized for psychiatric conditions.
The evaluation refers to the individual’s functioning over the month preceding the assessment.

Scale Validity

The validity of the GAF scale is confirmed through a correlation between the total score and the degree of autonomy and activity level an individual maintains, with a correlation coefficient of r = 0.65 (p = 0.01). Furthermore, a negative correlation was found between the number of symptoms associated with schizophrenic psychosis and the individual’s level of functioning. With a cutoff score of 40, it was observed that 84% of individuals who scored between 10 and 40 experienced a worsening of their condition—demonstrating the scale’s strong predictive capability.

Scale Reliability

To evaluate the reliability of the GAF scale, two independent psychiatrists conducted assessments and concluded that the scale’s reliability score was 0.74, a sufficiently high value. The test-retest reliability of the scale was also found to be strong.

References

Madianos, M., Economou, M., Peppou, L. E., Kallergis, G., Rogakou, E., & Alevizopoulos, G. (2012). Measuring public attitudes to severe mental illness in Greece: Development of a new scale. The European Journal of Psychiatry, 26(1), 55–67.
Pedersen, G., Urnes, Ø., Hummelen, B., Wilberg, T., & Kvarstein, E. H. (2018). Revised manual for the Global Assessment of Functioning scale. European Psychiatry, 51, 16–19.
Kleanthous, E. (2019). Exploring the relationship between needs, quality of life, and overall functioning in people with mental illness in Cyprus (Doctoral dissertation, National and Kapodistrian University of Athens, School of Health Sciences, Department of Nursing, Division of Mental Health and Behavioral Sciences).