| Click here or type alt 0 for a list of keyboard shortcuts ### Prior to making an appointment under Schedule A, an agency must require proof of an applicant's disability. What type of documentation (and by whom) is appropriate? Records, statements, or letters by a medical professional, a physician or other medically professional duly certified to practice medicine. Records, statements, or letters from a Federal agency or state agency that issues or provides disability benefits. Records, statements, or letters from a vocational rehabilitation counselor (State or private). All of the above. Select the correct response. Then select Next to continue.