Ensuring accurate toxicology results is crucial in clinical, forensic, and workplace settings. Specimen validity testing is vital in assessing urine sample integrity to prevent tampering, substitution, or adulteration. This process includes pre-analytical checks like visual inspection and temperature monitoring, as well as analytical tests for pH, specific gravity, and creatinine concentrations. These measures help identify diluted or altered samples, ensuring reliable results. Vigilance from sampling facilities, laboratorians, and clinicians is essential, as positive test outcomes can significantly impact medical decisions, legal proceedings, and employment, making sample integrity critical to trustworthy toxicology testing.