It is critical to teach students the use of control samples, blanks, standards, dummy analyses, and system suitability checks to increase confidence in measurements. This article is intended as a concise primer on these topics that faculty can distribute to and discuss with their laboratory and research students, particularly undergraduate students. Our experience suggests that students sometimes do not appreciate the fundamental differences between these concepts. This article directly addresses those differences and clarifies the distinct functions served by each. It is also important to illustrate to students how these techniques can be incorporated into experimental protocols. Therefore, we end the manuscript with several case studies that illustrate how the incorporation of controls, blanks, standards, and dummy analyses can improve the reliability of chemical measurements and increase confidence in experimental data. Our intention is that students can then extrapolate what they learn from these examples and thereby improve their overall approach to science. We strongly encourage the routine incorporation of these methods in undergraduate laboratory experiments, both for their pedagogical value in developing good scientific habits and also to increase a student’s confidence in his or her ability to obtain correct results. While a discussion of overall experimental design issues such as sampling, reproducibility, factorial design, and randomization are outside the scope of this report, sources that discuss these topics extensively are referenced to provide a more complete introduction to experimental methods.
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