Important skills for medical researcher
We need more researchers in rheumatology. 

EDIT: In the comments, you asked what skills you'd need to attract the attention of a potential supervisor when applying for a research elective in your upper years (prior to graduation).

Research electives for medical students are offered to those meeting a specific grade criterion. You must be able to meet that to even qualify. No amount of "passion" will give you this chance. Once you're in that pool of candidates, then it's largely a turkey shoot. In my university, the electives coordinator hands out a list of topics available in labs and units and students choose three projects in descending order of preference. Then, a matching process handles the details. The student receives an assignment and off they go. In some cases, students approach a potential supervisor about six months prior and expresses a desire to take the elective under his or her supervision. Then, a small bespoke project is crafted. This takes time, but often results in a more meaningful experience (not to mention a more lasting relationship between the student and the supervisor).

I generally assume that medical students undertaking research electives in my unit are devoid of research skills and we train them from the ground up. If you came to us stating, say, that you had skills in the measurement of nuchal translucency on ultrasound, we would still ask you to train under us, but expect that your pick-up of those skills would be faster than usual. There is no shame in stating that you don't know how or what to do. That's the point of the elective.

What base skills do we expect? (1) Good communication skills, both oral and written. I don't want to correct your grammar on the poster or teach you how to speak clearly before an audience. (2) Good literature search skills, as you'll be reading up on a lot of previous work. (3) Solid understanding of the foundational aspects of the research topic. If you're working on the management of asbestosis, I expect that you know the anatomy and physiology of the respiratory system as well as basic pathology of inflammation, etc. (4) Being able to work in teams. You'll likely be the most junior member of the team and I don't want you disrupting some of the more complex research projects under way.

Over the long therm, I've found these skills relevant to my own career:


Learn how to be a good clinician. Then, maintain a clinical load. Continuing to care for patients allows you to stay grounded not in what you do but WHY you do it. You can get lost in a Western blot and miss the adverse impact that achy joints have on a grandmother of five. I work in public health, but still see breast cancer patients. It's one thing to understand the effect that a drug has on millions of women. It's quite another to explain to a woman that her 13-year-old daughter does not need a mammogram just because Angelina Jolie was concerned about breast cancer.
Learn how to be a good teacher. Then, maintain a teaching load. You need to help train the new generation, much like the older generation trained you.
Learn how to network and collaborate. Good clinical research is rigorous. Great clinical research is collaborative.
Every so often, spend some time away from the lab and immerse yourself in a refugee camp or a medical mission. The lab is good for the brain; the immersion is good for the soul.


Good luck to you.

PS. 


  I believe I have sufficiently detailed knowledge of the medical content to work in the field.


Spoken like a true second year medical student.