I remember, there are a lot of studies about the (supposed) psychological traits of persons who believe in "conspiricy theories". Getting to the big parts, I still have some criticism of the study

1. You use a sample of students. No matter how lage the number are, do you really believe students are representative of the entire population of "conspiricy believers"?
2. How could you messure intellectuall humility?
3. The correlation between agreeableness and belief in conspiracy theories is easily explained by the fact that you will most likely get a lot of strange looks if you confess your conspiratorial beliefs in an academic environment. I doubt that this result would be transferable to other environments such as "normal" workspaces, nights out in pubs, and the like.