Texas Health and Safety Code - HEALTH & SAFETY § 42.0047. Estimated Glomerular Filtration Rate Reporting

(a) A laboratory that performs a serum creatinine test on a sample from a person 18 years of age or older shall also calculate and include in the reported results the person's estimated glomerular filtration rate or the results of an alternative equivalent calculation measuring kidney function if the laboratory receives along with the sample all relevant clinical information about the person necessary to calculate the person's estimated glomerular filtration rate or perform an alternative equivalent calculation.  A physician requesting a serum creatinine test shall provide to the laboratory all relevant clinical information about the person necessary to calculate the person's estimated glomerular filtration rate or perform an alternative equivalent calculation unless the physician determines that the calculation is unnecessary.

(b) The requirements under Subsection (a) do not apply to: