I was a participant in a medical research study and was paid for my service. What Principal Business code do I use for this income which was reported to me on a 1099-MI

[Opus 17 · Accepted solution]

In most cases this is not self-employment income, unless you make a habit of being a medical guinea pig.  Don't enter the 1099-MISC on the business side.  Instead, enter it on the personal side under other misc income.  After entering the 1099-MISC there is a page of special circumstances.  Check research subject, and then check that no services were required.

[estfhtrh]

How do i deduct mileage for this income?

[aaronc879]

You don't if you claimed it as "other income". You have to claim it as self employed income to deduct mileage. Then you would have to pay self employment tax which is expensive. Try it both ways and see which costs you more. Technically if you do studies as your primary source of income you should be claiming as self employed.

[Kerplunker]

I actually do medical clinical trials full time. Human guinea pig here. I bought a sprinter van to travel to the clinics because it was cheaper than flights and hotels. I live at home with my parents but I have a business tax ID and report the income as self employment income. I might be gone for a month let's say doing a trial in Nebraska and then leaving Nebraska to do a trial in Florida and then ultimately coming back home to California to take a break or just during down time. I was going pretty hard traveling from study to study with no real personal time in between gigs for about 4 months. How much of  the mileage and camp fees can I deduct? I'm thinking all of it (maybe outside of driving out out of my way to check out something here and there). I kept mile logs from leaving my parents home straight to the clinic. I also did two trials before I got the van where I did buy a flight, hotel and rental car. I assume I can write all that off too