Axis V - Global Assessment of Functioning scale (GAF), further evaluation of the self-report version.

ABSTRACT

OBJECTIVE: The study aimed to examine agreement between patients' and professional staff members' ratings on the Global Assessment of Functioning scale (GAF). METHODS: A total of 191 young adult psychiatric outpatients were included in a naturalistic, longitudinal study. Axis I and axis II disorders were assessed by means of the Structured Clinical Interview for DSM-IV. Before and after treatment, patients and trained staff members did a GAF rating. Agreement between GAF ratings was analyzed using the intra-class correlation coefficient (ICC). RESULTS: The overall intra-class correlation coefficients before and after treatment were 0.65 and 0.86, respectively. Agreement in different axis I diagnostic groups varied, but was generally lower before treatment as compared to after treatment (0.50-0.66 and 0.78-0.90, respectively). Excessive psychiatric co-morbidity was associated with the lowest inter-rater reliability. Agreement, with respect to change in GAF scores during treatment, was good to excellent in all groups. CONCLUSION: Overall, agreement between patients' and professionals' ratings on the GAF scale was good before and excellent after treatment. The results support the usefulness of the self-report GAF instrument for measuring outcome in psychiatric care. However, more research is needed about the difficulties in rating severely disordered patients.