Prediction markets handle this nicely because of the flexibility you have in asking the question and also the fact they output a quantitative value to your question.
For example, we can ask:
"If risk X occurs, what will happen?"
- Impact A
- Impact B
- Impact C
We can also directly correlate the occurrence of a risk (or any other event) with impacts. To do so, we simply multiply the chances of the impact and the risk to understand the likelihood the impact will occur in association with that risk.
For example, we can ask: "Will risk X occur?" and let's say the current price is $75, representing a 75% chance the risk will occur. In a separate question, we can ask "Will impact X occur if risk X occurs?" and let's say the current price is $25, representing a 25% chance the impact will occur.
Multiplying (.25 * .75) the two, we get ~.19 or a 19% chance Impact X will occur.
Assessing the impacts of risks is important for decision makers to understand as it will directly influence what they may or may not want to do to mitigate a risk. For example if the likelihood of a risk is high but only non-harmful impacts have a high probability of occurring, it may not be necessary to mitigate the risk. But if the reverse is true, mitigating that risk may take on a higher priority.