The text explains that quality control directives are crucial for analysis but not enough to ensure statistical control, which is managed by quality assessment???a key part of quality assurance. Quali...The text explains that quality control directives are crucial for analysis but not enough to ensure statistical control, which is managed by quality assessment???a key part of quality assurance. Quality assessment helps maintain, detect, and suggest solutions for loss of statistical control. It includes internal methods, like analyzing duplicate samples and spikes, and external methods, such as laboratory certification by an agency.
The written directives of a quality control program are a necessary, but not a sufficient condition for obtaining and maintaining a state of statistical control. Although quality control directives ex...The written directives of a quality control program are a necessary, but not a sufficient condition for obtaining and maintaining a state of statistical control. Although quality control directives explain how to conduct an analysis, they do not indicate whether the system is under statistical control. This is the role of quality assessment, the second component of a quality assurance program.