The variables were included in succeeding steps: (a) model 1 predicted psychopathology from only sex and age, (b) CTQ-SF score was added for model 2, (c) educational years was added for model 3, (d) age of schizophrenia onset was added for model 4, (e) antipsychotic dose and MMSE score was added for model 5, and (f) plasma oxytocin levels were added for model 6. Here, OXT is linked to schizophrenia.