I think the only research he did was just experimenting with different auditing techniques on preclears.
I always thought it was unlikely that he industriously studied different races and different primitive tribes. (Remember in The Fundamentals of Thought how he refers to blacks and Asians as "the brown and yellow people?")
You know, one of my grandmother's husbands, Ron, used to work with Hubbard. Ron told me this story about how he went up to Hubbard and said, "I've noticed you haven't produced any courses on how to do research." And Hubbard said, "That's right. That's because I do the research." And Ron said to Hubbard, "But that means it's nobody else's game but yours." Hubbard said, "That's right, it is my game." To which Ron replied, "Well, fuck that! I want my own game." And he quit Scientology after that.