What is the optimal neuropsychological test battery for schizophrenia in China?

BACKGROUND: The MATRICS consensus cognitive battery (MCCB) has been widely used to evaluate cognitive deficits in schizophrenia (SCZ), however, no study has formally examined the validity of the MCCB in Chinese SCZ. This study compared Chinese SCZ patients with healthy Chinese controls on the MCCB and some additional neurocognitive tests to determine if the Chinese MCCB is an optimal battery to assess the cognitive deficits in Chinese SCZ patients.

METHOD: The study enrolled and examined 230 patients met DSM-IV criteria for SCZ and 656 healthy controls matched for gender, age and education. Besides the MCCB, we also included some additional neurocognitive tests that have been widely used in patients with schizophrenia. We selected MCCB and non-MCCB tests with large effect size, to assemble a new "optimal battery" and compared its performance with that of the standard MCCB.

RESULTS: Comparing the putative "optimal" battery with the original MCCB, more patients with SCZ were identified as cognitively impaired according to the criteria of GDS ≥ 0.50 for the optimal battery (166 vs 135, or 72.2% vs 58.7%). The rate of cognitive impairment according to MCCB GDS in patients with SCZ who were currently working, ever worked and never worked are 45.5%, 61.6% and 70.8% (p = 0.051), whereas the optimal battery GDS showed 56.4%, 74.8%, 91.7% (p = 0.003), respectively.

CONCLUSIONS: Our study needs validation with independent samples but suggests that the current "optimal" cognitive battery could be more sensitive than the widely used MCCB in detecting SCZ related cognitive impairment in China.