 An example includes federal programs that offer HIV/Aids treatment and require that the participants be victims of such diseases.It is usually the recipient's responsibility to determine how to determine such eligibility, such as establishing policy that requires an in-house doctor or laboratory to diagnose each prospective participant, accepting diagnoses from third-party doctors or laboratories, etc.However, certain agencies have included specific parameters for which the recipient should follow, as in the case of the Department of Housing and Urban Development (HUD) which states in the Code of Federal Regulations (CFR) that recipients of certain HUD housing subsidy programs must obtain specific income verification documents to prove participant eligibility, such as W-2 payroll forms, a federal income tax return, etc.