Depressive symptoms frequently occur during the course of schizophreniThis study explored the relationships between schizophrenia symptomatology and 3 measures of depression. 81 drug-free inpatients with acute schizophrenia were assessed with the positive and negative syndrome scale (PANSS), the Calgary depression scale for schizophrenia (CDSS), and the Hamilton Rating Scale for Depression (HAM-D). The depressive subscale of PANSS (PANSS-D) was also considered as a 3rd scale for measuring depression. A principal component analysis of PANSS items identified 5 clinical dimensions of schizophrenia called negative, positive, anxio-depressive, excitement, and disorganization and others. The anxio-depressive dimension (PANSS-ad) was strictly identical with the PANSS-D. Scores on CDSS and HAM-D were highly inter-correlated and highly correlated with the PANSS-ad. Furthermore, while scores on CDSS were correlated only with this dimension, scores at HAM-D were also positively correlated with the negative dimension and negatively correlated with the excitement dimension. Results suggest that PANSS evaluation itself may be sufficient to give a correct approximation of the depression in schizophrenia.