Psychological Medicine

Original Articles

The causal relationships between neurocognition, social cognition and functional outcome over time in schizophrenia: a latent difference score approach

M. Hoea1 c1, E. Nakagamia2, M. F. Greena3 and J. S. Brekkea2

a1 Department of Social Welfare, College of Social Science, Keimyung University, Daegu, South Korea

a2 School of Social Work, University of Southern California, Los Angeles, CA, USA

a3 Department of Psychiatry and Biobehavioral Science, University of California at Los Angeles, VA Greater Los Angeles Healthcare System, Los Angeles, CA, USA

Abstract

Background Social cognition has been identified as a significant construct for schizophrenia research with relevance to diagnosis, assessment, treatment and functional outcome. However, social cognition has not been clearly understood in terms of its relationships with neurocognition and functional outcomes. The present study sought to examine the empirical independence of social cognition and neurocognition; to investigate the possible causal structure among social cognition, neurocognition and psychosocial functioning.

Method The sample consists of 130 individuals diagnosed with schizophrenia. All participants were recruited as they were admitted to four community-based psychosocial rehabilitation programs. Social cognition, neurocognition and psychosocial functioning were measured at baseline and 12 months. The empirical independence of social cognition and neurocognition was tested using confirmatory factor analysis (CFA) and the possible causal structure among social cognition, neurocognition and psychosocial functioning was investigated using latent difference score (LDS) analysis.

Results A two-factor model of social cognition and neurocognition fit the data very well, indicating the empirical independence of social cognition, whereas the longitudinal CFA results show that the empirical independence of neurocognition and social cognition is maintained over time. The results of the LDS analysis support a causal model that indicates that neurocognition underlies and is causally primary to social cognition, and that neurocognition and social cognition are causally primary to functional outcome.

Conclusions Social cognition and neurocognition could have independent and distinct upward causal effects on functional outcome. It is also suggested that the approaches for remediation of neurocognition and social cognition might need to be distinct.

(Received July 15 2011)

(Revised March 02 2012)

(Accepted March 05 2012)

(Online publication April 05 2012)

Correspondence

c1 Address for correspondence: M. Hoe, Ph.D., Assistant Professor, Department of Social Welfare, College of Social Science, Keimyung University, 2800 Dalgubeoldearo, Dalseo-Gu, Daegu 704-701, South Korea. (Email: maanse@kmu.ac.kr)

Metrics