Objective: Development of a scale to assess patients' social functioning, the Personal and Social Performance scale (PSP).
Method: PSP has been developed through focus groups and reliability studies on the basis of the social functioning component of the DSM-IV Social and Occupational Functioning Assessment Scale (SOFAS). The last reliability study was carried out by 39 workers with different professional roles on a sample of 61 psychiatric patients admitted to the rehabilitation unit. Each patient was rated independently on the scale by the two workers who knew them best.
Results: The PSP is a 100-point single-item rating scale, subdivided into 10 equal intervals. The ratings are based mainly on the assessment of patient's functioning in four main areas: 1) socially useful activities; 2) personal and social relationships; 3) self-care; and 4) disturbing and aggressive behaviours. Operational criteria to rate the levels of disabilities have been defined for the above-mentioned areas. Excellent inter-rater reliability was also obtained in less educated workers.
Conclusion: Compared to SOFAS, PSP has better face validity and psychometric properties. It was found to be an acceptable, quick and valid measure of patients' personal and social functioning.