Fig. 4
Effect of amisulpride augmentation therapy on the scores of Scale for the Assessment of Negative Symptoms (SANS) and Clinical Global Impression (CGI). a SANS score. b–d CGI-S, CGI-I, and CGI-E scores. SANS score showed no difference between two groups at week 12 or week 6 (a). At week 12, the amisulpride group had lower CGI-S, CGI-I and CGI-E scores than the placebo group (F = 20.37, P < 0.0001, Cohen’s d = 0.91; F = 5.75, P = 0.02, Cohen’s d = 0.80; F = 19.02, P < 0.0001, Cohen’s d = 1.06; respectively). However, after Bonferroni correction, only CGI-S and CGI-E scores still showed significant between-group differences (both PBonferroni < 0.0001) (b–d). At week 6, the amisulpride group had lower CGI-S and CGI-E scores than the placebo group (F = 10.93, P = 0.001, PBonferroni = 0.003, Cohen’s d = 0.72; F = 8.98, P = 0.004, PBonferroni = 0.01, Cohen’s d = 0.73) (b–d). *P < 0.05, **P < 0.01, ***P < 0.001; ns non-significant