Canadian Society for Medical Laboratory Science (CSMLS) Practice Exam

What is precision in a laboratory context?

1. Reproducibility of the value

2. Closeness of the result to the true value

3. Coefficient of true value

4. Sample error

The correct answer is: Reproducibility of the value

In a laboratory context, precision refers to the reproducibility of measurements. This means that if a test is repeated multiple times under the same conditions, precision is demonstrated by how consistently the results are when compared to one another. For example, if a laboratory test is performed multiple times and yields results that are very close to each other, then that test is considered precise, even if those results are not close to the actual or true value of what is being measured. The other options highlight different concepts: - Closeness of the result to the true value refers to accuracy, which is distinct from precision as it deals with how correct a result is rather than how consistent it is. - Coefficient of true value is not a standard term in laboratory science; typically, coefficients relate to correlation or variance, not precision. - Sample error indicates various errors that may occur during sample collection or processing, not the consistent reproducibility of result measurements. Therefore, the understanding of precision as described in the correct choice is critical for evaluating the reliability and quality of laboratory tests and experiments.