relationship between reliability and validity

If the scale is reliable it tells you the same weight every time you step on it as long as your weight has not actually changed. To better understand this relationship, let’s step out of the world of testing and onto a bathroom scale. Precision - ability to measure stable and consistent results on the same trials d. Reliability and validity are closely related. Validity - something’s ability to measure accurately, can be confirmed by another test measurement c. However, it cannot give a good result unless it is consistent. Reliability - something’s ability to measure stable and consistent results on the same trial b. However, a test cannot be valid unless it is reliable.Īnother way to think of it is that a test can give a consistent, poor result. But that doesn’t mean that it is valid, or measuring what it is supposed to measure. A test can be reliable without being valid.

A test can be reliable, meaning that the test-takers will get the same score no matter when or where they take it, within reasonably analogous circumstances. Switching back to testing, the situation is essentially the same. Reliability and validity are closely related. For the scale to be valid and reliable, not only does it need to tell you the same weight every time you step on the scale, but it also has to measure your actual weight. If that is the case, this is an example of a scale that is reliable, or consistent, but not valid.

However, if the scale is not working properly, this number may not be your actual weight. A test can be reliable, meaning that the test-takers will get the same score no matter when or where they take it, within reasonably analogous circumstances. Validity is all about accuracy in your measurements, while reliability determines consistency. Reliability and validity are closely related. Reliability (or consistency) refers to the stability of a measurement scale, i.e.

Relationship between reliability and validity