Differentiation of Psychotic From Nonpsychotic Psychiatric Inpatients: The Rorschach Perceptual Thinking Index

Development and preliminary validation of a brief behavioral measure of psychotic propensity

Extensive research demonstrates that the dimensional assessment of psychotic manifestations is a primary strength of the Rorschach inkblot task, which provides an in vivo sample of problem-solving behavior and normative standards concerning the logic and coherence of thought processes and the typicality of perceptual representations. This article presents foundational research for the Thought and Perception Assessment System (TPAS), a Rorschach-based system designed to assess solely for disordered thinking and perceptual aberrations using either the standard 10-card set of inkblots or alternative 3-, 4-, and 5-card short forms. Using data from three patient samples (ns = 61, 93, and 133) and one nonpatient sample (n = 118), we document the equivalence of mean scores across the full and short-form card sets. We also document satisfactory interrater reliability and validity for the full and short forms, as well as strong part-whole reliability coefficients between the short forms and the full form. Consistent with psychometric theory and the principle of aggregation, each type of coefficient decreased as a function of decreasing the number of cards. We discuss implications and future applications in research and clinical assessment.

Cognitive-perceptual deficits and symptom correlates in first-episode schizophrenia

Background

Thought disorder and visual-perceptual deficits have been well documented, but their relationships with clinical symptoms and cognitive function remain unclear. Cognitive-perceptual deficits may underscore clinical symptoms in schizophrenia patients.

Aim

This study aimed to explore how thought disorder and form perception are related with clinical symptoms and cognitive dysfunction in first-episode schizophrenia.

Setting

Forty-two patients with a first-episode of schizophrenia, schizophreniform or schizoaffective disorder were recruited from community clinics and state hospitals in the Cape Town area.

Methods

Patients were assessed at baseline with the Rorschach Perceptual Thinking Index (PTI), the Positive and Negative Syndrome Scale (PANSS) and the MATRICS Cognitive Consensus Battery (MCCB). Spearman correlational analyses were conducted to investigate relationships between PTI scores, PANSS factor analysis-derived domain scores and MCCB composite and subscale scores. Multiple regression models explored these relationships further.

Results

Unexpectedly, poor form perception (X- %) was inversely correlated with the severity of PANSS positive symptoms (r = -0.42, p = 0.02). Good form perception (XA%) correlated significantly with speed of processing (r = 0.59, p < 0.01), working memory (r = 0.48, p < 0.01) and visual learning (r = 0.55, p < 0.01). PTI measures of thought disorder did not correlate significantly with PANSS symptom scores or cognitive performance.

Conclusions

Form perception is associated with positive symptoms and impairment in executive function during acute psychosis. These findings suggest that there may be clinical value in including sensory-perceptual processing tasks in cognitive remediation and social cognitive training programmes for schizophrenia patients.

Antipsychotic treatment and the Rorschach Perceptual Thinking Index (PTI) in psychotic disorder patients: Effects of treatment

The Rorschach-based Perceptual Thinking Index (PTI) is used to identify and rate features of psychotic disorders, but effects of antipsychotic treatment on such ratings is not clear. Accordingly, we examined potential effects of antipsychotic drugs on PTI measures in 114 patients with a psychotic or bipolar-I disorder. Use and doses of antipsychotic drugs (as chlorpromazine-equivalent [CPZ-eq] mg/day) were unrelated to PTI total or subscale scores in any diagnostic group. PTI scores were independently and significantly associated with psychotic symptomatic severity (PANSS score) and less with female sex. These findings support the validity and value of the PTI in identifying features of psychosis even in the presence of antipsychotic treatment.

Relationship between the Rorschach Perceptual Thinking Index (PTI) and the Positive and Negative Syndrome Scale (PANSS) in psychotic patients: a validity study

The aim of this study is to demonstrate the validity of the Rorschach Perceptual Thinking Index (PTI) in the assessment of reality testing in patients with psychosis. We evaluated the relationship between the PTI criteria and the Positive and Negative Syndrome Scale (PANSS) scores in 98 psychotic disorder affected patients. Thirty four were evaluated during the acute episode (AP) and 64 were chronically treated and stable (CP). The PANSS positive score resulted significantly higher in AP than in CP group, but no significant difference was found in the PTI score. The PTI positively correlated with the PANSS total score. The PTI1 and PTI2 criteria significantly correlated with the PANSS negative score, the PTI4 and PTI5 with the positive. The Rorschach variable X-% significantly correlated with the negative symptoms; the WSum6 with thought disorders; and the M- with delusions. PTI score, X-% and WSum6 predicted impaired judgment and insight. These results suggest that PTI is a valid instrument to assess impairment in reality testing, regardless of the patient׳s current psychiatric presentation. The presence of conceptual disorganization, delusions, lack of judgment and insight don׳t have effects on the PTI, supporting its strength as an assessment tool for psychotic disorders.