Schizophrenia is a severe and persistent mental illness that results in substantial burden and disability for the individuals who suffer from it, their families, and society. Social disability, in particular, is one of the most crippling aspects of the disorder that dramatically limits functioning and quality of life. Recently, social-cognitive impairments in emotional intelligence have shown to be promising potential contributors to social disability in schizophrenia, and consequently might serve as effective targets for treatment. However, measurement in this area has been limited, and no study has examined the longitudinal relationship between emotional intelligence and social disability in schizophrenia within an experimental context. This study makes use of baseline and 1 year follow-up data from an outpatient sample of individuals in the early course of schizophrenia (n = 57 at baseline, n = 47 at year 1) participating in a randomized-controlled trial of Cognitive Enhancement Therapy to investigate the psychometric properties of a promising new measure of emotional intelligence, the Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT), and elucidate its longitudinal relations with social disability in this population. A comprehensive psychometric analysis was used to examine the reliability, discriminant validity, and factor structure of the instrument with individuals with schizophrenia; and general linear modeling, including hierarchical linear regression, was used to examine the cross-sectional and longitudinal relations between MSCEIT performance and social disability after accounting for demographic, clinical, and cognitive confounds. Psychometric results generally supported the reliability and discriminant validity of the MSCEIT when applied to individuals with schizophrenia, but also revealed a potential shift in the latent factor structure of the instrument in this population. Analyses of relations with social disability indicated little to no cross-sectional associations between MSCEIT performance and social disability, and modest longitudinal associations between changes in these domains. In particular, significant relationships were observed between longitudinal improvements in emotion regulation and reductions in overall social disability (r = -.31) and household/family relationship problems (r = -.34). These relationships persisted after adjusting for demographic characteristics, neurocognitive function, and psychopathology. Tentative evidence from mediator analyses pointed to the possibility of longitudinal improvements in emotion regulation to serve as a mechanism by which Cognitive Enhancement Therapy achieves its beneficial effects on social disability, although reverse mediation could not be ruled out. Together these findings suggest that changes in emotion regulation may be uniquely associated with changes in social disability in schizophrenia. Future research will need to replicate these findings with larger and more heterogeneous samples, and focus on the development of additional measures to study broader domains of social cognition, beyond emotional intelligence, that may also bear relevance to social disability
