These are always question of "control". Generally speaking the following factors are important.
1. Behavioral: Does the company control or have the right to control what the worker does and how the worker does his or her job?
2. Financial: Are the business aspects of the worker’s job controlled by the payer? (these include things like how worker is paid, whether expenses are reimbursed, who provides tools/supplies, etc.)
3.Type of Relationship: Are there written contracts or employee type benefits (i.e. pension plan, insurance, vacation pay, etc.)? Will the relationship continue and is the work performed a key aspect of the business?