prior probability

prior probability,

n the extent of belief held by a patient and practitioner in the ability of a specific therapeutic approach to produce a positive outcome before treatment begins. This level of belief should be taken into consideration by the patient and practitioner to make a decision as to whether the treatment should be used or to permit the therapy to continue.

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probability

the basis of statistics. The relative frequency of occurrence of a specific event as the outcome of an experiment when the experiment is conducted randomly on very many occasions. The probability of the event occurring is the number of times it did occur divided by the number of times that it could have occurred. Defined as:$$\hbox{p}={\hbox{x}\over (\hbox{x+y})$$

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where

p = probability, x = positive outcomes, y = negative outcomes.

prior probability

estimation of the probability that a particular phenomenon or character will appear before putting the patient to the test, e.g. testing the probable productivity of a patient by testing its forebears.

subjective probability

the measure of the assessor's belief in the probability of a proposition being correct.

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prior probability

Decision making The likelihood that something may occur or be associated with an event based on its prevalence in a particular situation. See Medical mistake, Representative heurisic.