Abstract

Schizophrenia, characterised by profound psychotic symptoms, is among the most challenging mental disorders to assess and diagnose. Its core psychotic features include hallucinations and delusions. There is limited research on the Perceptual Thinking Index (PTI) among schizophrenic patients in the Rorschach test. Therefore, the purpose of this review was to assess studies related to the Perceptual Thinking Index (PTI) among schizophrenic patients in the Rorschach test, and to determine whether this instrument can reliably indicate the risk of schizophrenia. All databases, including PubMed, Science Direct, and Scopus, were searched using the keywords “Schizophrenia” and “Rorschach” for literature published from 1938 to the end of 2025. Screening and quality evaluation of articles were carried out independently by two reviewers. Of the 150 articles identified in the initial search, 15 met the inclusion criteria and were included in the final analysis. Findings indicate that colour-shading responses are considered among the most critical PTI variables using the multiple-sign approach. Hertz’s multiple-signs approach and Exner’s Perceptual Thinking Index are the most commonly used indices for assessing schizophrenic patients. A total PTI score of 8 or higher in the Rorschach test is a powerful predictor of schizophrenia.