Validity of Self-Rating Questionnaires Used for Assessing Self-Disorders? A Systematic Review

Self-disorders designate a group of nonpsychotic, trait-like, anomalous self-experiences. The "gold standard" for assessing self-disorders is largely considered to be the Examination of Anomalous Self-Experience (EASE). The EASE must be conducted as a semistructured interview, and it requires substantial knowledge of psychopathology and excellent interviewing skills. To bypass these demands, self-rating questionnaires are regularly used to assess self-disorders in research. However, it is not clear if these self-rating questionnaires are valid measures of self-disorders. The purpose of this systematic review was to assess the validity of self-rating questionnaires used for assessing self-disorders.

Following the PRISMA guidelines, we searched PubMed, Embase, and PsycInfo for studies that had used or developed self-rating questionnaires for assessing self-disorders.

Twenty-nine studies had used or developed self-rating questionnaires to assess self-disorders, involving a total of 8 different self-rating questionnaires. None of these self-rating questionnaires have been properly validated to measure self-disorders in relation to EASE.

Despite being frequently used in research, only 1 (IPASE: The Inventory of Psychotic-Like Anomalous Self-Experiences) of the 8 self-rating questionnaires has been attempted validated in relation to the EASE. Though a strong correlation was found between IPASE and EASE, the result cannot be considered valid because of profound methodological issues. We recommend that efforts to validate self-rating questionnaires are prioritized if they are to be used in research, and that results from studies using self-rating questionnaires are separated from those of EASE-based research as long as the self-rating questionnaires have not been properly validated in relation to the EASE.