The Personality Assessment Screener (PAS) is a self-descriptive, objective questionnaire intended for the identification of persons who require further clinical assessment, as well as for the rapid triage of various psychological disorders. The aim of this research is to check the sensitivity of the Personality Assessment Screener in differentiating the profile of clinical groups diagnosed with alcoholism, depression and schizophrenia. The research was conducted on a sample of 80 respondents who were hospitalized at the psychiatry department at the Clinical Hospital Center of the Sisters of Charity in Zagreb at the time of the research. Participation was voluntary and the respondents filled out the questionnaires as part of group therapy work. Several statistically significant differences were found between the groups, in a way that subjects with a diagnosis of depression had statistically significantly higher scores than others on the elements Negative Affect and Health Problems; subjects diagnosed with alcoholism and schizophrenia had statistically significantly higher scores than subjects with a diagnosis of depression on the Acting Out scale; subjects with a diagnosis of depression had statistically significantly higher scores than subjects with a diagnosis of alcoholism on the Suicidal Thinking scale and subjects with a diagnosis of alcoholism had statistically significantly higher scores than subjects from other groups on the Alcohol Problem scale. No statistically significant difference was found in the Total score and in the Psychotic Features, Social Withdrawal, Hostile Control, Alienation and Anger Control scales. In conclusion, the PAS proved to be largely successful in differentiating the profiles of clinical groups with diagnoses of alcoholism and depression, while its sensitivity in recognizing the profile of the clinical group with a diagnosis of schizophrenia was somewhat weaker.