|PT is a well-established tool for assuring and improving clinical laboratory performance. The effectiveness of PT is influenced by many factors. Interpretation of PT data impacts both individual laboratories and larger public health decisions, sometimes inappropriately.
Lead exposure has well-defined health impacts, and measurement of blood lead concentration is typically exclusively used for diagnosing and treating lead poisoning. The National Blood Lead PT Program serves over 800 laboratories employing a variety of analytical techniques and QC goals. In this presentation, data from this program are used to illustrate what PT data can tell us—and what it may appear to, but actually does not.