A double-blind clinical and chemical study of 131 hospitalized psychotic patients, totally removed geographically from the center at which chemical analyses were performed, demonstrated an inverse relationship between the quantity of cerebrospinal fluid glycoprotein neuraminic acid and the severity of schizophrenia, with a high concordance between chemical levels, changes in clinical condition, and family history. In addition, changes in cerebrospinal fluid glycoprotein hexose were related inversely to clinical estimates of depression.Abstract Teaser