Performance of patients with different schizophrenia subtypes on the Synthetic House–Tree–Person Test

We explored differences in performance on the Synthetic House–Tree–Person Test between people with mainly positive symptoms and those with mainly negative symptoms of schizophrenia and, further, aimed to provide a basis for the diagnosis of schizophrenia symptom type. Participants were 58 people receiving treatment for schizophrenia, and we asked them to complete the Scale for the Assessment of Positive Symptoms, the Scale for the Assessment of Negative Symptoms, and the Synthetic House–Tree–Person Test. There were significant differences in results on the Synthetic House–Tree–Person Test between the group with positive symptoms, the group with a mix of positive and negative symptoms, and the group with negative symptoms. There were 12 features of participants' drawings, such as big hands, which were correlated with hallucinations and delusions in positive symptoms, and 9 features, such as trees in a landscape, which were correlated with avolition and anhedonia in negative symptoms. Our study results suggest differences in performance on the Synthetic House–Tree–Person Test between these different symptom subtypes of schizophrenia; hence, the features that appear in drawings made during the test may contribute to the diagnosis of symptoms of people with schizophrenia.