Lead time bias is the bias that occurs when two tests for a disease are compared, and one test (the new, experimental one) diagnoses the disease earlier, but there is no effect on the outcome of the disease—it may appear that the test prolonged survival, when in fact it only resulted in earlier diagnosis when compared to traditional methods. It is an important factor when evaluating the effectiveness of a specific test.
Other articles related to "time, times, lead time bias, lead time":
... Consider the time series of an independent variable and a dependent variable, with observations sampled at discrete times ... In many common situations, the value of at time depends not only on but also on its past values ... Commonly, the strength of this dependence decreases as the separation of observations in time increases ...
... Korzybski was born in Warsaw, Poland which at that time was part of the Russian Empire ... a new theory of humankind mankind as a "time-binding" class of life (humans perform time binding by the transmission of knowledge and abstractions ...
... Unix time, or POSIX time, is a system for describing instances in time, defined as the number of seconds that have elapsed since midnight Coordinated Universal Time (UTC), 1 ... It is neither a linear representation of time nor a true representation of UTC ... Unix time may be checked on some Unix systems by typing date +%s on the command line ...
... For more details on this topic, see Lead time bias ... cases a person will die at the same time, because we diagnosed the disease earlier with screening the survival time since diagnosis is longer with screening but life span has not been ... Looking at statistics of survival time since diagnosis, screening will show an increase (this gain is called lead time) ...
... Even if in both cases a person will die at the same time, because the disease was diagnosed early with screening, the survival time since diagnosis is longer with ... Looking at raw statistics, screening will appear to increase survival time (this gain is called lead time) ... If we do not think about what survival time actually means in this context, we might attribute success to a screening test that does nothing but advance diagnosis ...
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