Tex. Civ. Prac. & Rem. Code § 74.105

Consent to medical care that appears on the disclosure panel's list requiring disclosure shall be considered effective under this chapter if it is given in writing, signed by the patient or a person authorized to give the consent and by a competent witness, and if the written consent specifically states the risks and hazards that are involved in the medical care or surgical procedure in the form and to the degree required by the disclosure panel under Section 74.103.