The Personal and Social Performance scale (PSP) is widely used to assess social functioning with 4-domain scores and a global score in patients with schizophrenia. However, internal and external responsiveness of the PSP is largely unknown limiting its use as an outcome measure.

The purpose of this study was to examine internal and external responsiveness of the PSP in inpatients with schizophrenia receiving treatments in the acute phase.

Eighty patients were conducted the PSP and the Clinical Global Impression-Severity (CGI-S) at admission and at discharge. The standardized effect size (ES), the standardized response mean (SRM), and paired t-test were used for examining internal responsiveness. We estimated correlations between the changes in scores of the PSP and those of the CGI-S using Pearson's r for investigated external responsiveness.

For internal responsiveness, the ESs and the SRMs of the domains were 0.74–1.74 and 0.68–1.72, respectively. The values of the ES and the SRM in the global score were 1.72 and 1.74, respectively. The paired t-tests showed statistically significant difference (P < 0.001) for the score changes of the four domains and the global score. Regarding external responsiveness, fair and moderate to good correlations (r = 0.35–0.74) were found among the changes in the 4-domain scores and the global score with the those of the CGI-S.

The PSP has sufficient internal responsiveness and substantial external responsiveness in inpatients with schizophrenia receiving treatments at the acute wards. The PSP is useful as an outcome measure for detecting changes of social functioning over time.

The authors have not supplied their declaration of competing interest.