Discuss the issues a decision maker should consider when determining the significance level to use in a hypothesis test.

The decision maker should base his decision on whether the results contain enough information to doubt the conventional wisdom, which is if conventional wisdom was used to make the null hypothesis. Critical region of a hypothesis test are all outcomes that reject the null hypothesis and rule in favor of the alternative hypothesis. In cases like these it is better to make a type I error than type II. If you are looking if there is anything out there you might set the critical value higher, say 1 instead of 0.5. So if the research finds something at that level, then they work on research design after making that decision.