laboratorydeveloped

A laboratory developed test, often abbreviated as LDT, is a diagnostic test that is developed and validated within a single laboratory. Unlike commercially available tests, LDTs are not subject to the same rigorous pre-market review processes by regulatory bodies like the U.S. Food and Drug Administration (FDA). These tests are typically used for specific patient populations or to detect novel or rare diseases for which no commercially available test exists.

The development of an LDT involves meticulous design, validation, and quality control procedures performed by the laboratory itself. This includes establishing analytical validity, which ensures the test accurately measures the intended analyte, and clinical validity, which confirms the test's ability to correctly diagnose or rule out a condition. Laboratories offering LDTs are generally accredited by organizations such as the College of American Pathologists (CAP) or Clinical Laboratory Improvement Amendments (CLIA) to ensure high standards of quality and safety.

While LDTs provide valuable diagnostic options, their regulatory oversight differs from that of in vitro diagnostic (IVD) products. This distinction has led to ongoing discussions and evolving regulatory approaches regarding the oversight of LDTs to ensure patient safety and test reliability. LDTs are particularly important in areas of personalized medicine and rare disease diagnostics where innovation is rapid and specialized testing is required.