Which certificate allows a laboratory to conduct moderate- to high-complexity laboratory testing temporarily?

The correct choice is the certificate of registration, which allows a laboratory to perform moderate- to high-complexity laboratory testing temporarily. This certificate is issued under the Clinical Laboratory Improvement Amendments (CLIA) framework and serves as a transitional permit for laboratories that are in the process of achieving full compliance with more comprehensive licensing requirements.

The certificate of registration is crucial because it is a necessary step for laboratories that might not yet meet the stringent guidelines set for compliance or accreditation but are still capable of conducting certain tests. This allows them to operate while they work towards meeting the standards required for a more permanent certificate, thereby enabling them to continue testing while achieving the necessary qualifications.

In contrast, the other certificates have specific purposes: a certificate of waiver is designed for labs performing only tests categorized as “waived,” which are typically simple tests with low complexity; a CLIA certificate of compliance is awarded to labs that have met all federal CLIA regulations, and a certificate of accreditation is granted to those accredited by a recognized organization and deemed compliant with more rigorous standards. Each of these other options does not provide the flexibility of temporarily conducting moderate- to high-complexity testing, which is why the certificate of registration is the correct answer.