In middle and high school, science teachers emphasized the importance of precision, accuracy, and validity in measurement. It may have seemed redundant in years past, but these principles have become even more important in academic research. Whether you’re an interested hobbyist or a science lecturer, every higher ed professional connected to the sciences must know why precision, accuracy, and validity are vital in research.

Replicating Precision

Precision refers to the nature of results in a series. When a scientist performs an experiment, they must be able to reproduce the same results every time. If they manage to reproduce the same or minimally different results in a series of tests, the results are precise. A lack of precision can lead to imperceptible random errors that yield widespread results.

Suppose you want to know how much hydrogen is in a gaseous mixture. If you test the sample several times and get significantly different results each time, you know your answers are imprecise. Something may be wrong with the measuring device or with the method itself. If the device is off, a scientist can use calibration gas to reset the sensors. If the technique is wrong, it will take some more theorizing to find a better, more practical solution.

Aiming for Accuracy

Imagine a target with a bullseye in the middle. Accuracy defines how close the darts are to the bullseye. While you can have replicable precision, these results may not be accurate to the truth—you could be doing the same thing wrong over and over again, getting the same answers.

Accuracy is how close a measurement is to its actual value. Imprecision is easy to notice when you have an erroneous value. Determining accuracy is a bit trickier. Maladjusted equipment and human error can lead to incorrect results that fail to represent reality.

Establishing Validity

Validity refers to the soundness of the theoretical framework backing a method. The experimental method in any new test relies upon well-established procedures and practices in the scientific community.

For example, if you want to measure a saltwater solution's volume, you will need a beaker demarcated with measured notches. If you put the beaker on a scale instead, you will measure the weight in grams, not the volume in milliliters. Your results would be invalid if you recorded the solution's weight in place of the volume since the method did not correlate with the outcome.

Knowing why precision, accuracy, and validity are vital in researchhelps students, staff, lecturers, and researchers do their work. Without these guiding principles, increasingly complex experiments would fall apart and have no direction.