Hi!
I am reapplying this year, and have been working in healthcare for a number of years. I do not work giving direct care to patients, but still work closely with patients from the administrative side. While I may not have a definitive answer, from my experience I found that it was helpful in showing that I was dedicated to the field of medicine and knowing what it was like to work within healthcare. However, it was not necessarily the most helpful in interviews. I found that they were not all that interested in what I had done, but more interested in how I thought, and if I had any unique experiences with patients because of my job.
After going through exit interviews I understand more as to why they did not ask me questions pertaining to my job. It is more important to them that you will be a good fit for the program and be successful within the program than having knowledge as to how to do a specific job. I don't agree with this fully, as I understand that through school one will learn to be a doctor and work within the field, but will be lacking fundamental knowledge of being an employee, working for a company, or being a business owner.
I feel that there's a lot to be gained from working in the healthcare field prior to matriculating. But, many schools do not find this necesary. So, if this is important to you and they are not asking questions, then take time at the end of the interview when they ask if there's anything else you would like to add to interject why an experience was important to you, unique, and will help you be a better doctor and student within their program.