Introduction: The objective of evidence based medicine (EBM) is to contribute to medical decision making by providing the best possible information in terms of validity and relevance. This allows evaluation in a specific manner of the benefits and risks of a decision.
Methods: The limitations and hazards of this approach are discussed in relation to a clinical case where the diagnosis of pulmonary embolism was under consideration. The individual details and the limited availability of some technical procedures illustrate the need to adapt the data of EBM to the circumstances. The choice between two diagnostic tests (d-dimers and ultrasound of the legs) and their optimal timing is analysed with integration of the consequences for the patient of the treatments proposed. This allows discussion of the concept of utility and the use of sensitivity analysis.
Conclusions: If EBM is the cornerstone of rational and explicit practise it should also allow for the constraints of real life. Decision analysis, which depends on the same critical demands as EBM but can also take account of the individual features of each patient and test the robustness of a decision, gives a unique opportunity reconcile rigorous reasoning with individualisation of management.