Born of necessity: the dynamic synergism between advancement of analytic methods and generation of new knowledge.

Serious studies of the results of clinical interventions, such as those of heart valve surgery, employ mathematical and statistical methods and modes of expression and presentation that are complex. I, along with my colleagues, am guilty of developing some of these methods. However, in this address I trace the more than three centuries of development that has led to present methodology, demonstrating that each increase in complexity was born of the necessity to reflect clinical reality. These methods include survival analysis, and particularly its central theme, the hazard function, from its invention by a storekeeper during the Plague to the multiple phase hazard method developed by us. Importantly, contemporary methods permit patient-specific predictions that are useful for recommending therapy and for informed patient consent. In contemporary medicine, molecular-level research would seem to hold the promise of making observational clinical studies obsolete; yet a flurry of so-called Outcomes Research has emerged. However, the danger now is that new forces and philosophies are driving that interest that are not as strongly tuned to the necessities of improving individual patient care and longitudinal outcome as has been the case in the past.