Many universities, as a form of bio-certification, require students to have either updated testing or a medical document dated within the last three years that states their diagnosis - however this is sometimes absurd for individuals with certain disabilities. For instance, if someone if born with a congenital limb difference, their doctor may not note "ongoing treatment" within the last three years on a medical document unless they had received a new prosthetic, yet limbs don't grow back and that person may be visibly disabled to an accommodations officer without having the biocertification paperwork to prove their disability.