Background: Subjective cognitive complaints, or neurocognitive insight, reflect to patients' awareness of cognitive functioning. In schizophrenia, these complaints show inconsistent links with objective cognition, psychiatric symptoms, and illness insight. The Subjective Scale to Investigate Cognition in Schizophrenia (SSTICS), a validated self-report tool developed in Canada and used internationally, enables a homogeneous synthesis. Objective: This meta-analysis examined whether subjective complaints measured with the SSTICS are associated with objective cognition, psychiatric symptoms, and illness insight, and reviewed its factorial structure. Method: We conducted a meta-analysis following PRISMA guidelines. Systematic searches of PubMed, Web of Science, and Google Scholar identified studies using the SSTICS in psychiatric populations. Eligible studies compared patients to healthy controls and/or examined correlations with cognition, symptoms, or illness insight or conducted factor analyses of the SSTICS domains. Results: Twenty-five studies (N = 3,205) met criteria. Schizophrenia patients reported more cognitive complaints than controls (d = 0.746). No significant correlation emerged with global objective cognition (r = 0.105). Complaints were unrelated to positive, negative, or general symptoms but showed a moderate association with depressive symptoms (r = 0.300) and a small one with illness insight (r = 0.155). Factor analyses consistently identified 3 domains: memory, attention, and daily living. Conclusions: SSTICS-based complaints are substantial in schizophrenia but largely dissociated from objective cognition, reflecting impaired neurocognitive insight. Instead, they are more strongly linked to depressive symptoms, suggesting complaints reflect emotional distress rather than actual deficits. Findings support refining SSTICS subscales and extending investigations to other psychiatric populations.
Contexte:: Les plaintes cognitives subjectives, c’est-à-dire la conscience des déficits neurocognitifs, correspondent à la perception que les patients ont de leur fonctionnement cognitif. Dans le cas de la schizophrénie, ces plaintes montrent des liens variables avec la cognition objective, les symptômes psychiatriques et la conscience de la maladie. La Subjective Scale to Investigate Cognition in Schizophrenia (SSTICS), un outil d’autodéclaration validé, mis au point au Canada et utilisé à l’échelle internationale, permet d’en offrir une synthèse homogène.
Objectif:: La présente méta-analyse visait à déterminer si les plaintes subjectives mesurées avec la SSTICS sont associées à la cognition objective, aux symptômes psychiatriques et à la conscience de la maladie, et à en examiner la structure factorielle.
Méthode:: Une méta-analyse a été réalisée conformément aux lignes directrices PRISMA. Des recherches systématiques dans PubMed, Web of Science et Google Scholar ont permis de recenser des études menées auprès de populations psychiatriques ayant utilisé la SSTICS. Les études admissibles comparaient les patients à des témoins sains et examinaient les corrélations avec la cognition, les symptômes ou la conscience de la maladie, ou comportaient des analyses factorielles des domaines de la SSTICS.
Résultats:: Vingt-cinq études (N = 3 205) répondaient aux critères. Les patients atteints de schizophrénie rapportaient davantage de plaintes cognitives que les témoins (d = 0,746). Aucune corrélation significative n’a été observée avec la cognition objective globale (r = 0,105). Les plaintes n’étaient pas associées aux symptômes positifs, négatifs ou généraux, mais présentaient une corrélation modérée avec les symptômes dépressifs (r = 0,300) et une corrélation faible avec la conscience de la maladie (r = 0,155). L’analyse des facteurs a permis de relever trois domaines constants : la mémoire, l’attention et la vie quotidienne.
Conclusions:: Les plaintes évaluées à l’aide de la SSTICS sont fréquentes chez les personnes atteintes de schizophrénie, mais demeurent généralement indépendantes de la cognition objective, ce qui suggère une altération de la conscience des déficits neurocognitifs. Elles sont toutefois plus étroitement liées aux symptômes dépressifs, indiquant que ces plaintes reflètent davantage la détresse émotionnelle plutôt que de véritables déficits. Ces résultats plaident en faveur du raffinement des sous-échelles de la SSTICS et de l’élargissement des recherches à d’autres populations psychiatriques.
Keywords: cognition; insight; meta-analysis; schizophrenia.
Schizophrenia and Cognitive ComplaintsPlain Language SummaryThis paper presents a meta-analysis, which is a research method that combines results from many separate studies to provide a clearer and more reliable overall conclusion. We examined how people with schizophrenia report their own cognitive difficulties, such as problems with memory, attention or planning, and how these self-reports relate to actual performance on cognitive tests. All studies included in this meta-analysis used the same questionnaire, the Subjective Scale to Investigate Cognition in Schizophrenia (SSTICS), to measure subjective cognitive complaints. Across studies, people with schizophrenia reported significantly more thinking and memory difficulties than people without the illness. However, these complaints did not strongly match objective test results, meaning that how patients feel about their cognitive abilities often does not reflect how they perform on standardized tests. We also found that these complaints were not closely tied to positive or negative psychotic symptoms. Instead, they showed a moderate association with depressive symptoms: individuals who felt more depressed tended to report more cognitive problems. A small association was also found between cognitive complaints and insight into illness. Together, these findings suggest that subjective cognitive complaints in schizophrenia may reflect emotional distress rather than true awareness of cognitive deficits. This highlights the importance of evaluating both patient experiences and objective cognitive skills when planning treatment, rehabilitation and support.