I've had the same question since that is the weakest portion of my application. As far as I know, in general, there is not a tremendous quantity of radiology research for students to acquire. It seems that most of the research is with radiation oncology and radiation physics. However, the more competitive a residency gets, every little extra, including research experience, counts. I doubt the research issue will approach what is needed for dermatology, for example, any time soon.
So to answer you question, radiology research would make you stand out, rather than being a prerequisite for matching. Let's see what the next poster sez... 😀
