S100B and schizophrenia: The meta-regression of S100B serum levels with clinical parameters in schizophrenia revealed significant effects for the covariates illness duration (βillness duration = 0.0537, p = 0.01), bias index (βbias index = 0.3023, p = 0.001) as well as PANSS total (βPANSS total = −0.0435, p = 0.001), positive (βPANSS positive = −0.1273, p = 0.02) and general psychopathology (βPANSS general = −0.0965, p < 0.001) scores, but not for any of the other regressions calculated (see Table 2, Figure 5).