People such as doctors, dentists, veterinarians, lawyers, accountants, contractors, subcontractors, public stenographers, or auctioneers who are in an independent trade, business, or profession in which they offer their services to the general public are generally independent contractors. However, whether they are independent contractors or employees depends on the facts in each case. The general rule is that an individual is an independent contractor if the person paying for the work has the right to control or to direct only the result of the work and not how it will be done. The earnings of a person who is working as an independent contractor are subject to self-employment tax. For more information on determining whether you are an employee or independent contractor, see Pub. 15-A, Employer's Supplemental Tax Guide.
This information can be found in Publication 334, Tax Guide For Small Business.