Prognosis Definition

Disease and Prognostic Indicators
Two areas where this type of prognosis prediction, or the use of prognostic indicators, is with Hodgkin's lymphoma and Non-Hodgkin lymphoma.  Specifically with Non-Hodgkin lymphoma, physicians have developed the International Prognostic Index to predict patient outcome.

Prognostic scoring is also used for other cancer outcome predictions. A Manchester score is an indicator of prognosis in small cell lung cancer.

Other medical areas prognostic indicators are used is in Drug-Induced Liver Injury (DILI) (Hy's Law) and use of an exercise stress test as a prognostic indicator after myocardial infarction.

End of Life
Large areas of medicine are still missing statistical figures on the exact prognosis - in these matters the physician's previous experiences largely guides pronouncements in this matter. Medical studies have demonstrated that most doctors are overly optimistic when giving prognostic information, that is, they tend to overstate how long the patient might live. For patients who are critically ill, particularly those in an intensive care unit, there are numerical prognostic scoring systems that are more accurate. The most famous of these is the APACHE II scale. However, this scale is most accurate in the seven days prior to a patient's predicted death.

Knowing the prognosis helps determine whether it makes more sense to attempt certain treatments or to withhold them, and thus plays an important role in end-of-life decisions.

History
Medieval European physicians would sometimes use numerology to calculate a prognosis, using the Sphere of Petosiris.

For the great 19th century physicians, particularly the French school, the main aim of medicine was not to cure disease, but rather to diagnose it and achieve a satisfying prognosis of the patient's chances. Only several decades later did the focus of efforts in Western medicine shift to curing disease.