To make clinically relevant recommendations for chest X-ray testing in acute psychiatric admissions, this study examined the current practice of this screening test in patients admitted to a University Hospital. The records of the 332 first consecutive admissions to the psychiatric ward were assessed. In 200 patients (60%) a chest X-ray was requested. The X-ray film was normal in 81.5% of patients. The remaining subjects presented abnormalities: nonrelevant in twenty-seven (13.5% of the total), and relevant in eleven (5.5%). Since all these relevant abnormalities were already known, in no cases was the test followed by changes in therapy or by additional diagnostic procedures. In almost all cases this screening test was of no practical value. Our findings challenge the systematic indication of chest X-ray in acute psychiatric patients, and suggest that the number of tests performed and the cost of medical care could be reduced by a more efficient use of past medical history and physical examination criteria, without compromising the quality of patient care.