WHAT ARE REPRODUCIBILITY AND REPEATABILITY? - SCIENCE - 2024

Reproducibility and repeatability are basic principles of the scientific method; Through both it is possible to confirm experiments, as well as to establish international and national measurement standards. Reproducibility has to do with the replication of a test in the hands of the scientific community of a certain branch.

The main objective is to obtain results under the same conditions, in order to check the veracity of an experiment. According to experts, this quality must be evaluated in the long term. On the other hand, repeatability indicates the percentage of variability present in the measurement instruments used in a given test.

It is even estimated that this variability is less since it is more precise. In any case, both methods are considered as important pillars for hypothesis testing in disciplines such as engineering, statistics, chemistry, physics, and other sciences.

What is a reproducibility and repeatability study?

Reproducibility and repeatability studies rely on statistics to evaluate the dispersion in the results obtained after an experiment.

That is why the subsequent analysis of independent research groups is preferred, which will confirm the level of reproducibility and repeatability of the test performed.

In view of the above, it is necessary to point out some important features in each of the processes:

Reproducibility

This indicates the variation due to the measurement equipment that was used during the test, which must preserve the same conditions and the same operators or members of the research team. The change will be given by the measurement conditions.

Despite the fact that in some disciplines this concept may be more or less rigorous, in general it is considered that what is relevant is a certain degree of consistency in the results. Some considerations that should be taken into account in this case are the following:

-It is important to point out which are the variations during the process, among which the measurement principle, the method, the operator, the instrument used, the place, the time and the general conditions of the laboratory stand out.

-The results must be expressed quantitatively.

-Within the scientific community it is considered a relatively simple process and easy to replicate, although it involves constant review of the results.

Repeatability

As mentioned above, repeatability indicates the deviation that can occur due to a measuring instrument used during the experiment. Therefore, its precision is evaluated when the test is repeated under the same conditions and in a determined period of time.

Likewise, some considerations that must be taken into account when conducting the study can be highlighted:

-You should try to reduce the variations that may be caused by the operator.

-The same measurement system and the same operator must be used.

-The same place in which the experiment was carried out should be considered.

-It is necessary to do several repetitions in a certain period of time.

-The results must be reflected in a quantitative way.

On the other hand, although both methods are discussed in the field of science, they are also applied in the social sciences, although the results may vary due to the changes that the objects of study always present.

Other elements

In addition to the above, the reproducibility and repeatability study depends on other factors of equal importance:

Measurement accuracy

Indicates the closeness of the measurement result and the value to be measured.

Digital measuring instrument

That tool that will reflect the result digitally. At this point it should be mentioned that it is important to detail the operation of these types of devices so that they do not affect the experimentation process.

Work pattern

It includes the components that are part of the calibration and measurement routine. This has to do directly with the instruments in the laboratory.

Calibration

It is the relationship that exists in the values ​​obtained by means of the operator and / or the measuring instruments, between the processes contemplated in the work pattern.

Instrument accuracy

It has to do with the accuracy that is expected from the tools used for testing.

Sensitivity

It is related to the change of measurement of an instrument due to some variation during the test.

Results

This particular point is important because it depends on a careful analysis, as it will confirm or not the success of the applied experimental design.

In this case, not all results are derived from a measuring instrument, but may also depend on the operator, the different measurements or whether the result was corrected or not.

Reproducibility in metrology

Reproducibility allows the reduction of uncertainty in the measurement system, so it seeks maximum accuracy. As it uses the reproduction of the same result under various conditions, it depends on whether the studies carried out are carried out in a certain period of time.

It is also applicable to various fields such as engineering, statistics, industry and even law. That is why it is considered an important factor because it allows establishing national and international standards.

Some instruments used range from the simplest such as rulers and compasses, to those with a higher level of complexity, such as microscopes and telescopes.

The application of reproducibility is also evidenced in the so-called International Vocabulary of Metrology or VIM, which is a reflection of internationally established and understood measurements.

Reproducibility in chemistry

The reproducibility procedure in chemistry also requires a series of steps to obtain measurements and other results.

You can take as an example determining the mass of an element:

1- The scale plate is placed on the weight to obtain a certain value.

2- Then the same will be done but with the object or element in question. In this way, two different results will be obtained that must be contrasted. It is in this step when the calibration of values ​​is manifested.

3- Carry out this same procedure over the next few days, as it will help to find the existing variations.

Both in this and in any other case regarding reproducibility, it is important not to neglect the value of the statistics in the process, since it will serve as a control element in the experiment and the results.

References

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