Literature regarding employment in patients with schizophrenia, particularly on factors associated with employment status, is lacking in Malaysia. In this study, among the demographic, clinical and cognitive variables studied; marital status, educational level, mean scores of negative symptoms, Digit Span and RAVLT and Trail Making Tests were found to show significant association with employment status on bivariate analyses. However, when entered into a logistic regression model, only cognitive variables ie. Trail A and B, Digit Span and RAVLT were significant predictors of employment status.
The results from this study support the role of cognitive function, particularly attention, working memory and executive functioning on attaining and maintaining employment in persons with schizophrenia as measured by the RAVLT, Digit Span and Trail Making Tests. These findings are consistent with those from other studies which showed association of cognitive impairment with unemployment [18, 28, 29, 33]. McGurk and Meltzer (2000)  also found that those who were employed full time did significantly better on tests of working memory, vigilance and executive functioning than those who were unemployed. This relationship persisted even after education was controlled for. Among the different domains of cognitive function, several specific domains have been shown to be associated with functional outcome more often than the others. A review by Green and colleagues involving 37 studies in this area  confirmed an earlier review  and concluded that cognitive domains that were most often found to be associated with social function included secondary verbal memory, immediate memory, executive functioning and vigilance.
Besides employment, cognitive impairment is also associated with the broader functional outcomes among patients with schizophrenia [27–29, 34]. In a review paper evaluating neurocognitive functions as predictors and correlates of functioning among persons with schizophrenia by Green  found strong and consistent associations between cognitive functions and functioning in schizophrenia. Verbal memory, executive functioning and vigilance were found to be associated with different aspects of functional outcome. These findings were again confirmed by Green in a meta-analysis involving a larger number of such studies  as well as by other researchers [26, 29, 35]. With regard to whether different functioning areas are determined by intact specific cognition functions, independent living skills were found to be associated with executive function , vocational functioning with attention and verbal memory , and employment status was strongly predicted by intact verbal learning and memory, executive functioning as well as overall intelligence . In addition to personal and vocational functioning, social skills were also found to be dependent on certain intact cognitive domains. For example, social problem-solving was found to be associated with executive functioning and attention .
In this study, there was no significant association between overall psychopathology, positive or negative symptoms and employment. This result is not inconsistent with similar studies where a strong correlation between psychopathology and employment has not been consistently established. Green et al  reported that in most studies, schizophrenic symptoms were not significantly associated with functional outcome. This is particularly more so for positive symptoms as compared to negative symptoms where some studies found negative symptoms but not positive symptoms to be associated with unemployment in schizophrenia [16, 20, 39–41]. Negative symptoms in schizophrenia are seen by some as the result of cognitive deficits that impair motivation and insight and hinder therapeutic alliance and compliance . In this study, negative symptoms which were found to be associated with employment status through bivariate analysis were removed from the regression model. This may have been partly due to the problem in eleciting accurate information on negative symptoms as at least half of the participants came to the clinic without other informants. There was a possibility of minimization of negative symptoms among some participants as it is understood that there may be social values attached to negative symptoms.
As this was a cross-sectional study, we can only conclude that there is an association between cognition and employment. We are unable to ascertain causation or directionality. It is possible that unemployment is caused by poor cognitive functions or vice versa. Unemployment has a multitude of possible effects on mental health ranging from reduced self-confidence and social isolation to anxiety and depression. These factors may have an adverse influence on cognitive processes. Furthermore, employment calls upon the exercise of cognitive functions by repetition or training, another form of cognitive remediation. It is however more likely that unemployment in patients with schizophrenia is the result of poor cognitive functioning rather than the cause of it.
Other limitations of this study include the reliance of diagnosis of illness on that made from clinical judgement without use of a diagnostic tool which may have affected the accuracy of diagnosis of the participants enrolled in the study. Secondly, this study was done at a tertiary psychiatric setting in the most populous city in Malaysia, therefore, may not represent other patient populations from other parts of the country.