Insight in schizophrenia: meta-analyses of the relationships between insight and functioning, and insight and quality of life

Professional Doctorate - Doctor of Clinical Psychology (DCP)Background: The clinical importance of insight in schizophrenia is in its ability to predict or determine outcome. This question has so far not been clearly answered in respect to quality of life and functioning. A review of the literature assessing the relationships between insight, and both quality of life and functioning, suggested complex and inconsistent relationships. Aims: The aim of this study was to synthesise the data using meta-analytic techniques, on insight and functioning, and insight and quality of life, to determine whether the inconsistency and disparity found amongst the studies, when combined, may uncover a relationship between these variables. Method: For inclusion in the two meta-analyses, studies had to report on a relationship between insight and quality of life or functioning in individuals with schizophrenia. Studies also had to be in English and published in a peer-reviewed English language journal. A literature search was conducted in the electronic databases of Medline and PSYCINFO from the period of January 1985 to December 2010. Reference lists of recent reviews and key papers were also screened for relevant studies, and a manual search of key journals was conducted for the period of June 2007 to December 2010. Correlation coefficients were the measure of effect size, and the random-effects model was utilised when computing the effect sizes for both meta-analyses. All analyses were computed using the Comprehensive Meta-Analysis package. The data was tested for heterogeneity using the Q statistic. In the event that the test for heterogeneity was significant, a search for moderator variables was conducted. Results: A modest positive relationship was found between insight and functioning, such that good insight correlated with good functioning, but a paucity of prospective data means that the ability of insight to predict functioning remains unknown. It is also unclear as to what extent this correlation between insight and functioning is mediated by symptoms. The results showed no significant relationship between insight and quality of life. Discussion: The implications of these findings are discussed, as well as possible explanations for the lack of relationship. It appears that the body of research would benefit from a shift in focus from purely cross-sectional research to more prospective data, which would yield important information on the predictive importance of insight in regards to functioning and quality of life. Some prospective studies were published too recently to be included in the sample, and some presented results that could not be converted into correlation coefficients. It should be noted however that these gave slender support for the ability of insight to predict functioning at follow-up. It is suggested that the most effective way to improve outcomes such as functioning and quality of life for individuals with schizophrenia may be to design interventions that address these outcomes directly, rather than via insight