I believe that a link to Google Scholar and an explanation of what it is should feature prominently on every page of this site. Many questions can be answered by a quick search there, and the rest will profit from the initial research that becomes easily possible with this tool. This explanation should include the fact that most academic institutions have access to many online journals, and that a trip to the next university library will make most of the articles readable for the general public through the computers in the library.
To answer your question: I have no knowledge of the subject matter, but a Google Scholar search yielded several articles on the topic of conspiracy theories, some of which deal with the phenomenon from an empirical perspective.
For example, one study found, that certain personal characteristics, such as fear of unemployment, correlated with belief in conspiracy theories, while occupational category did not correlate with belief in conspiracy theories.
If you did further into the Google Scholar search results, you might find further, possibliy contradictory, findings and opinions on the topic.
As to your observation that many medical professionals from your family believe in creationism, and the hypothesis you deduce from this observation that maybe medical professionals are more likely to accept such ideas, I would say that this is a classic case of not recognizing a confounding variable. All the medical professionals you know come from the same family. Since religious beliefs are mostly acquired through familial habits, it is most likely that it is your family, not medicine, that correlates with belief in creationism. What defines your family and could correlate with a similar belief in other people, you might be able to recognize if you take a step back an look at your family in relation to who else lives in your country: what is your family's social status, religious tradition, ethnicity, where do you live, how are your children educated etc. etc. From all the factor that you find, you could then build a working hypothesis and test it. Some factors have been tested in the linked article, others you might find discussed elsewhere.