The regional distribution of white matter (WM) abnormalities in schizophrenia remains poorly understood, and reported disease effects on the brain vary widely between studies. In an effort to identify commonalities across studies, we perform what we believe is the first ever large-scale coordinated study of WM microstructural differences in schizophrenia. Our analysis consisted of 2359 healthy controls and 1963 schizophrenia patients from 29 independent international studies; we harmonized the processing and statistical analyses of diffusion tensor imaging (DTI) data across sites and meta-analyzed effects across studies. Significant reductions in fractional anisotropy (FA) in schizophrenia patients were widespread, and detected in 20 of 25 regions of interest within a WM skeleton representing all major WM fasciculi. Effect sizes varied by region, peaking at (d=0.42) for the entire WM skeleton, driven more by peripheral areas as opposed to the core WM where regions of interest were defined. The anterior corona radiata (d=0.40) and corpus callosum (d=0.39), specifically its body (d=0.39) and genu (d=0.37), showed greatest effects. Significant decreases, to lesser degrees, were observed in almost all regions analyzed. Larger effect sizes were observed for FA than diffusivity measures; significantly higher mean and radial diffusivity was observed for schizophrenia patients compared with controls. No significant effects of age at onset of schizophrenia or medication dosage were detected. As the largest coordinated analysis of WM differences in a psychiatric disorder to date, the present study provides a robust profile of widespread WM abnormalities in schizophrenia patients worldwide. Interactive three-dimensional visualization of the results is available at www.enigma-viewer.org.

The gap between the demand and delivery of mental health services in mainland China can be reduced by validating freely available and psychometrically sound psychological instruments. The present research examined the Chinese version of the 21-item Depression Anxiety Stress Scales (DASS-21). Study 1 administered the DASS-21 to 1,815 Chinese college students and found internal consistency indices (Cronbach's alpha) of .83, .80, and .82 for the Depression, Anxiety, and Stress subscales, respectively, and .92 for the total DASS total. Test-retest reliability over a 6-month interval was .39 to .46 for each of the 3 subscales and .46 for the total DASS. Moderate convergent validity of the Depression and Anxiety subscales was demonstrated via significant correlations with the Chinese Beck Depression Inventory (r = .51 at Time 1 and r = .64 at Time 2) and the Chinese State-Trait Anxiety Inventory (r = .41), respectively. Confirmatory factor analyses supported the original 3-factor model with 1 minor change (nonnormed fit index [NNFI] = .964, comparative fit index [CFI] = .968, and root mean square error of approximation [RMSEA] = .079). Study 2 examined the clinical utility of the Chinese DASS-21 in 166 patients with schizophrenia and 90 matched healthy controls. Patients had higher Depression and Anxiety but not Stress subscale scores than healthy controls. A discriminant function composed of the linear combination of 3 subscale scores correctly discriminated 69.92% of participants, which again supported the potential clinical utility of the DASS in mainland China. Taken together, findings in these studies support the cross-cultural validity of the DASS-21 in China. (PsycINFO Database Record

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A common limitation of neuroimaging studies is their small sample sizes. To overcome this hurdle, the Enhancing Neuro Imaging Genetics through Meta-Analysis (ENIGMA) Consortium combines neuroimaging data from many institutions worldwide. However, this introduces heterogeneity due to different scanning devices and sequences. ENIGMA projects commonly address this heterogeneity with random-effects meta-analysis or mixed-effects mega-analysis. Here we tested whether the batch adjustment method, ComBat, can further reduce site-related heterogeneity and thus increase statistical power. We conducted random-effects meta-analyses, mixed-effects mega-analyses and ComBat mega-analyses to compare cortical thickness, surface area and subcortical volumes between 2897 individuals with a diagnosis of schizophrenia and 3141 healthy controls from 33 sites. Specifically, we compared the imaging data between individuals with schizophrenia and healthy controls, covarying for age and sex. The use of ComBat substantially increased the statistical significance of the findings as compared to random-effects meta-analyses. The findings were more similar when comparing ComBat with mixed-effects mega-analysis, although ComBat still slightly increased the statistical significance. ComBat also showed increased statistical power when we repeated the analyses with fewer sites. Results were nearly identical when we applied the ComBat harmonization separately for cortical thickness, cortical surface area and subcortical volumes. Therefore, we recommend applying the ComBat function to attenuate potential effects of site in ENIGMA projects and other multi-site structural imaging work. We provide easy-to-use functions in R that work even if imaging data are partially missing in some brain regions, and they can be trained with one data set and then applied to another (a requirement for some analyses such as machine learning).

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Findings support the validity of the 5-factor structure of BNSS-rated negative symptoms across diverse cultures and languages. These findings have important implications for the diagnosis, assessment, and treatment of negative symptoms.

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Using Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), previous study showed significant gender differences for cognitive deficits in immediate and delayed memory in schizophrenia patients. However, RBANS does not include reasoning and problem solving, and social cognition. These cognitive functions can significantly affect the outcomes and daily life in patients. This study examined the gender differences of cognition using the measurement and treatment research to improve cognition in schizophrenia (MATRICS) consensus cognitive battery (MCCB), especially focusing on reasoning and problem solving, and social cognition in schizophrenia patients. The results showed that healthy controls exemplified better cognition than patients in both genders in all examined MCCB scores. Male healthy controls had better reasoning and problem solving and working memory than females, but these gender differences were not presented in schizophrenia patients. Also, male schizophrenia patients showed worse cognition than females on social cognition, processing speed, verbal learning and visual learning. Our results support that male schizophrenia patients had more cognitive impairment than females on reasoning and problem solving, social cognition, processing speed, working memory, verbal learning and visual learning.