Deterministic effects are characterised by:
- A threshold dose below which no effect is seen
- Worsening of the effect as dose increases over the threshold
- Always occurring once the threshold dose is reached
- Different effects, tissues and people have different threshold doses for deterministic effects
All early effects, and most normal tissue late effects are deterministic.
Stochastic effects account for the remaining late effects:
- They have no threshold dose
- They increase in likelihood as dose increase
- Their severity is not dose related
- There is no dose above which stochastic effects are certain to occur
Stochastic effects include radiation carcinogenesis and hereditary effects.