Revisiting Rorschach test and Minnesota Multiphasic Personality Inventory-II patterns in Kraepelinian vs. DSM-wise Schizophrenia: How They Differ and What It Means for Diagnosis.

Objective: This retrospective chart review study aimed to investigate the differences in the Rorschach test and Minnesota Multiphasic Personality Inventory (MMPI)-II profiles among patients with Kraepelinian schizophrenia, those with DSM-wise schizophrenia, and controls. Kraepelinian schizophrenia is characterised by a chronic, deteriorative disease course and a predominance of negative symptoms.

Methods: Patients with Kraepelinian schizophrenia were selected based on medical record reviews. We then compared their Rorschach test and MMPI-II results with those of the DSM-wise schizophrenia group and the control group.

Results: The Rorschach test revealed a significant increase in DV2 score and a decrease in D score in patients with Kraepelinian schizophrenia compared to those with DSM-wise schizophrenia. In the MMPI-II profiles, patients with Kraepelinian schizophrenia exhibited an elevated L relative to those with DSM-wise schizophrenia.

Conclusion: Our results suggested the value of revisiting psychological tests in clinically delineated subgroups, such as Kraepelinian schizophrenia. Although patients fall under the same diagnostic category of schizophrenia, considering different phenotypes is important when interpreting psychological test outcomes. Additionally, our study indicated that both schizophrenia groups did not show as many abnormalities as expected compared to controls. This highlights the potential value of revisiting established profiles of certain psychological tests and calls for further research on other psychological tests.