Favourable results of the computer-aided diagnosis of peripheral bronchial carcinoma lead to a simplified scheme for calculation fo diagnosis, basing upon X-ray symptoms. This scheme was tested in the Zentralinstitut für Krebsforschung (ZIK) in 102 pateints and in the Forschungsinstitut für Lungenkrankheiten und Tuberkulose (FLT) in 101 patients. These patients had coin lesions of the lung with unknown diagnoses. The histological diagnoses later proved were compared with the calculated diagnoses. In ZIK there were correct diagnosis in 92.16% (in 96.53% of the carcinomas, in 44.4% of the tuberculomas and in all benign tumors), while in FLT 85.53% of the coin lesions were correctly classified (89.13% of carcinomas, 79.31% of the tuberculomas and all benign tumors). The comparison with the clinical-histological diagnoses showed a clear improvement of the accuracy by the calculated diagnoses. The method can be recommended for the basic diagnosis especially of peripheral bronchial carcinoma. It implies a reduction of the diagnostic delay, but it can not substitute the histologic investigation of the lesions.