Cognitive Complaints in Schizophrenia: A Meta-Analysis of Studies Using the Subjective Scale to Investigate Cognition in Schizophrenia (SSTICS): Les plaintes cognitives dans la schizophrénie : Une méta-analyse des études utilisant la Subjective Scale To Investigate Cognition in Schizophrenia (SSTICS)

Key findings from this study

• The study found that schizophrenia patients report substantially more cognitive complaints than healthy controls, despite these complaints showing negligible correlation with objective cognitive performance.
• The researchers demonstrate that subjective cognitive complaints associate more strongly with depressive symptoms than with positive, negative, or general psychiatric symptoms.
• The authors report that factor analyses consistently identified three SSTICS domains—memory, attention, and daily living—across the analyzed studies.

Overview

This meta-analysis synthesized 25 studies (N = 3,205) using the Subjective Scale to Investigate Cognition in Schizophrenia (SSTICS) to examine associations between patient-reported cognitive complaints and objective cognitive performance, psychiatric symptoms, and illness insight in schizophrenia. The SSTICS is a validated self-report instrument developed in Canada and applied across international psychiatric populations.

Methods and approach

The meta-analysis followed PRISMA guidelines. Systematic searches of PubMed, Web of Science, and Google Scholar identified eligible studies. Included studies either compared schizophrenia patients to healthy controls, examined correlations between subjective complaints and objective cognition/symptoms/illness insight, or performed factor analyses of SSTICS domains. The synthesis aggregated effect sizes and correlation coefficients across investigations.

Results

Schizophrenia patients reported significantly more cognitive complaints than controls (d = 0.746). Subjective complaints showed negligible correlation with global objective cognition (r = 0.105), indicating substantial dissociation between perceived and measured cognitive deficits. Complaints were unassociated with positive, negative, or general psychiatric symptoms but demonstrated moderate association with depressive symptoms (r = 0.300) and weak association with illness insight (r = 0.155).

Factor analyses consistently extracted three domains from the SSTICS: memory, attention, and daily living. This tripartite structure appeared robust across the included studies, supporting the measure's factorial validity. The consistency of this structure across samples suggests stable underlying domains within the instrument.

Implications

The strong patient-reported complaints coupled with negligible objective cognition correlations indicate impaired neurocognitive insight in schizophrenia. Complaints appear to reflect affective distress rather than actual cognitive deficits, as demonstrated by their moderate association with depressive symptoms. This dissociation suggests current SSTICS subscales may conflate emotional and cognitive dimensions, necessitating refinement to differentiate these constructs.

The weak association with illness insight contradicts assumptions that subjective complaints simply reflect metacognitive awareness. Future investigations should extend SSTICS validation to other psychiatric populations to determine whether this complaint-cognition dissociation is specific to schizophrenia or generalizes across conditions. Enhanced subscale specificity may improve the instrument's diagnostic and prognostic utility in clinical settings.

Scope and limitations

This summary is based on the study abstract and available metadata. It does not include a full analysis of the complete paper, supplementary materials, or underlying datasets unless explicitly stated. Findings should be interpreted in the context of the original publication.