This study was conducted to assess the use of the European preliminary criteria, the Breiman-classification tree and the American-European criteria for diagnosis of primary Sjögren's Syndrome (pSS) in daily practice. A retrospective analysis of 17 consecutive patients with pSS (European criteria) was performed evaluating the application of the Schirmer test, semiquantitative sialoscintigraphy, immunologic tests, including rheumatoid factor, antinuclear antibodies, Sjögren's syndrome autoantibodies (SS-A, SS-B) and lip biopsy. Out of the 17 patients with pSS according to the European criteria, 15 patients fulfilled the classification tree (=88.2%), and 4 patients fulfilled the American-European criteria (=23.5%, P = 0.001). In the four patients fulfilling the American-European criteria, a positive result of the sialoscintigraphy was not crucial for the diagnosis according to these criteria. In conclusion, the American-European criteria are more stringent than the European preliminary criteria. We assume the role of sialoscintigraphy to be reduced when applying the American-European criteria.