Faulstich M E, Brantley P J, Barkemeyer C A
Am J Psychiatry. 1984 Apr;141(4):584-6. doi: 10.1176/ajp.141.4.584.
The mean creatine phosphokinase level of 41 psychotic patients was significantly higher than that of 30 nonpsychotic psychiatric patients, as were their MMPI paranoia and schizophrenia scores. Their creatine phosphokinase level was negatively correlated with hysteria and psychopathic deviance.