Reliability and validity of the Personal and Social Performance scale in patients with schizophrenia

Abstract

ObjectiveThe construct validity and test–retest reliability of the Personal and Social Performance (PSP) scale were used to assess social functioning in a cohort of ethnically diverse UK patients with schizophrenia. MethodsA total of 73 patients with schizophrenia took part in the study. At baseline, the PSP, two symptomatology scales and two other functioning scales were administered. A subset of the sample (N=40) took part in a retest where the Clinical Global Impression—Severity (CGI-S) and PSP scales were administered 8–10days later. ResultsPSP significantly correlated with all other measures, Positive and Negative Syndrome Scale (PANSS), Global Assessment of Functioning (GAF) and Quality of Life Scale (QLS) at baseline (p<0.02) and with CGI-S at follow-up (p<0.01). In addition, the PSP scale was moderately sensitive to the severity of illness. Test–retest reliability for the PSP score was 0.45 and the scale was able to discriminate between known groups (mild and severe patients). ConclusionThe PSP was easy to administer in this predominantly inpatient cohort and was moderately correlated with all other functioning measures tested. Due to patient homogeneity, the test–retest reliability statistic of the PSP was lower than that observed in other studies.