We get this question a lot. When you moonlight, how you're compensated determines how you're taxed. If no taxes are taken out, you're considered an indepedent contractror, and you can write off your professional expenses directly against that income. If taxes are withheld, you're considered an employee.

So if you moonlight at the hospital where you are doing your training, you can't separate that income from your resident's salary to treat it as "moonlighting" income. Instead, you'll report all of your W-2 wages on Line 7 of your federal tax return.

Depending on your 1099-Misc income and the total of your unreimbursed professional expenses, why not just claim the bulk of those expenses directly against your 1099-Misc income on the Schedule C?

In other words, you can't take Schedule C (business) deductions against your W-2 moonlighting income. You'll have to see if you can use Schedule A job-related deductions against that income (subject to the 2% AGI floor rule).