New Standard for Medical Laboratory-Developed Tests (LDTs)
Medical laboratory professionals have a responsibility to provide services of the highest quality and integrity and to practice their profession with honesty, integrity, and reliability. Medical laboratory testing must be carried out to an appropriate standard and all work must be performed with a high level of skill and competence so as not to produce unreliable results, which could lead to patient harm. ¹
What are Medical Laboratory-Developed Tests (LDTs)?
There are some tests, for which no commercial methods are available or the commercial method is prohibitively expensive. Some laboratories may have more modern technologies that can provide a much superior test result to traditional methods. Laboratories therefore develop their own tests. Such tests are referred to as “in-house” or laboratory-developed tests (LDTs).
LDTs can be defined as tests developed (or modified) and used within a single laboratory to carry out testing on samples, where the results are intended to assist in clinical diagnosis or be used in making decisions concerning clinical management. As of 2017, no national level consensus guidance document existed on the topic of LDTs. While many laboratories can perform validation studies of these tests, there was no standard by which to assess their performance, quality, and reliability.
Minimum Requirements and Best Practices for LDTs
CSA Group developed Z316.8 Requirements for the design, development, and validation of laboratory-developed tests used for the screening, diagnosis, and management of clinical conditions, which specifies the minimum requirements and best practices for the development, validation, and use of LDTs in clinical and research laboratories for the screening, diagnosis, and management of clinical conditions. Published in 2018, this first edition provides requirements on the development and validation of LDTs that have not been subjected to an in-depth validation process.
The Standard is intended to be used by organizations and individuals that are developing LDTs for the purpose of providing results that can be used in the screening, diagnosis, or management of clinical conditions. This document represents consensus best practice for LDTs for all disciplines in laboratory medicine. It acts as a resource for any lab intending to develop tests in-house or use an in-house method for clinical reporting and for accreditation agencies that are setting best practice expectations for clinical labs.
Topics Covered in CSA Z316.8 at a Glance
¹Ethical practice in laboratory medicine and forensic pathology. Mohamed M. El-Nageh, et al. WHO Regional Publications, Eastern Mediterranean Series, 1999.