Validation of the Turkish Version of the "Functional Remission of General Schizophrenia" (FROGS) Scale

Objective: The concepts of functionality and remission in schizophrenia are being subject for a substantial amount of research. At the same time, an increasing number of scales are developed in our country and worldwide, which are intended to measure the level of functionality in severe mental disorders. Functional remission is an important goal of treatment, which provides possibility of an autonomous lifestyle for schizophrenia patients, allowing them to readapt to their relationships with parents, work life, other interpersonal communications and social environments. The "Functional Remission of General Schizophrenia" (FROGS) Scale was developed in French and is suitable for use in research as well as for clinical evaluation of patients. We intended to carry out a validity and reliability study on this scale in order to make it eligible for use in the conditions within Turkey. Methods: 102 schizophrenia patients, either inpatients or outpatients, receiving treatment in the Istanbul University, Istanbul Faculty of Medicine, Psychiatry Department, were included in the study. In this research, reliability of the "Functional Remission of General Schizophrenia" (FROGS) Scale was assessed by investigating the internal consistency coefficients and item analysis procedures of every subscale and interrater reliability coefficient, whereas validity was evaluated by factor analysis, content validity and criterion validity. In order to test the criterion and content validities in addition to the FROGS Scale, the Schizophrenia Quality of Life Scale (SQLS) was used and the Positive and Negative Syndrome Scale (PANSS) was aplied to determine the symptom severity. Results: Within the reliability analysis, the highest internal consistency coefficient of the scale (0.89) was found using Cronbach's Alpha method. The lowest internal consistency coefficient (0.86) was obtained with Guttman's split-half technique. The investigation of the item analysis results of the "Functional Remission of General Schizophrenia" (FROGS) Scale has shown that all of the items which the scale consists of are significant at 0.01 level when they are assessed using all three methods of item total, item remainder and distinctiveness (p<0.01). Therefore, it was decided that those items are excellent and they should be included in the scale, Criterion validity analysis was carried out between the FROGS Scale and the Quality of Life Scale and a high level of correlation was observed (r=0.82, p<0.0001). A good level of correlation was found between the FROGS Scale and PANSS, as well (r=-0.51, p<0.001). Conclusion: The Turkish version of the "Functional Remission of General Schizophrenia" (FROGS) Scale is a tool which can assess the functional remission of schizophrenia patients in a reliable and valid level. (Archives of Neuropsychiatry 2009,46 Supplement 15-24)