Neurocognition is moderately to severely impaired in patients with schizophrenia. However, the factor structure of the various neurocognitive deficits, the relationship with symptoms and other variables, and the minimum amount of testing required to determine an adequate composite score has not been determined in typical patients with schizophrenia.

Keefe RSE, Bilder RM, Harvey PD, Davis SM, Palmer BW, Gold JM, Meltzer HY, Green MF, Miller DD, Canive JM, Adler LW, Manschreck TC, Swartz M, Rosenheck R, Perkins DO, Walker TM, Stroup TS, McEvoy JP, Lieberman JA. Baseline neurocognitive deficits in the CATIE schizophrenia trial. Neuropsychopharmacology 2006, 31(9): 2033-2046.