Consequence for which the probability of occurrence depends on the absorbed dose: hereditary effects and cancer induced by radiation are considered to be stochastic effects. The term "stochastic" indicates that the occurrence of effects so named, would be random. This means that, even for an individual, there is no threshold of dose below which the effect will not appear, and the chance of experiencing the effect increases with increasing dose. WHO, 1989a RT all-or-none effect, quantal effect.