Many older concrete bridge decks in Europe, mostly built without transverse reinforcement, show a significant lack of shear capacity due to increasing traffic loads and changes in design. Strengthening the slabs for shear is difficult and very expensive. Thus, more reliable design methods are urgently needed to overcome the calculated safety deficit and in order to avoid unnecessary retrofitting. In this paper a new design method will be presented which gives at least 40 % higher shear capacities than current design rules (EN 1992-1-1:2004; Eurocode 2 Part 1 (2004), in the following EC2-1). This approach is based on the examination of full-scale tests of cantilever slabs and statistical evaluation of a database with test results of reinforced concrete slabs under concentrated loads. Next, this paper shows the advantages and limitations of probabilistic analysis.