I'm continuing an undergraduate research position even though I graduated at a hospital in the PECARN network. A quick google search showed me that Columbia is also a member of the PECARN network. To my understanding, many of these PECARN members use undergraduates to help screen and enroll patients in the ED setting. I would email the PECARN department and see if they are receptive to you working there for a gap year. It's probably not the clinical research you're looking for as its pretty much just screening patients as they come into the ED and you aren't really involved in the design of studies typically but it's an option. Feel free to ask any questions.