42 CFR § 493.1253 - Standard: Establishment and verification of performance specifications.
(i) Demonstrate that it can obtain performance specifications comparable to those established by the manufacturer for the following performance characteristics:
(2) Establishment of performance specifications. Each laboratory that modifies an FDA-cleared or approved test system, or introduces a test system not subject to FDA clearance or approval (including methods developed in-house and standardized methods such as text book procedures), or uses a test system in which performance specifications are not provided by the manufacturer must, before reporting patient test results, establish for each test system the performance specifications for the following performance characteristics, as applicable:
(iii) Analytical sensitivity.
(iv) Analytical specificity to include interfering substances.
(vi) Reference intervals (normal values).
(vii) Any other performance characteristic required for test performance.
(3) Determination of calibration and control procedures. The laboratory must determine the test system's calibration procedures and control procedures based upon the performance specifications verified or established under paragraph (b)(1) or (b)(2) of this section.
(c) Documentation. The laboratory must document all activities specified in this section.