A–C, The scatter plots show the relationships between the NAA concentrations (mmol/kg brain) of all patients and the severity of symptoms. The lines between the 95% confidence curves represent linear regression lines. A, The negative correlation between the NAA concentrations and BPRS scores (r = −0.59, P = .001). B, The relationship between the NAA concentrations and severity of negative symptoms (SANS scores) (r = −0.68, P < .001). C, The association (r = −0.41, P = .028) of NAA concentrations with the severity of positive symptoms (SAPS scores).