Which agency is responsible for approving new test methodologies, instruments, and reagents?

The Food and Drug Administration (FDA) is responsible for approving new test methodologies, instruments, and reagents in the United States. The FDA ensures that medical devices and diagnostic tests are safe and effective for their intended use before they can be marketed. This includes a thorough evaluation process that assesses the reliability, validity, and accuracy of the tests, as well as their performance in real-world clinical situations.

In contrast, other agencies mentioned in the options serve different roles. The Centers for Disease Control and Prevention (CDC) focuses on public health and safety, primarily involved in disease control and prevention efforts rather than test approval processes. The Clinical Laboratory Standards Institute (CLSI) works on developing standards and guidelines for laboratory testing processes but does not have the authority to approve test methodologies or instruments. Similarly, the World Health Organization (WHO) is an international health agency that addresses global health issues and supports guidelines and health initiatives but does not have the regulatory authority to approve medical tests or devices at a national level.