Question

If assessment results are highly valid, will they also be highly reliable.

If assessment results are highly reliable, they may or may not be valid.

In selecting an assessment, validity has priority over reliability.

Give example of each

Answer 1

◉ Reliability - The test must yield the same result each time it is administered on a particular entity or individual, i.e., the test results must be consistent.

It refers to the consistency and reproducibility of data produced by a given method, technique, or experiment. The form of assessment is said to be reliable if it repeatedly produces stable and similar results under consistent conditions. Consistency is partly ensured if the attribute being measured is stable and does not change suddenly. However, errors may be introduced by factors such as the physical and mental state of the examinee, inadequate attention, distractedness, response to visual and sensory stimuli in the environment, etc. When estimating the reliability of a measure, the examiner must be able to demarcate and differentiate between the errors produced as a result of inefficient measurement and the actual variability of the true score. A true score is that subset of measured data that would recur consistently across various instances of testing in the absence of errors. Hence, the general score produced by a test would be a composite of the true score and the errors of measurement.

◉ Validity - The test being conducted should produce data that it intends to measure, i.e., the results must satisfy and be in accordance with the objectives of the test.

It refers to the ability of the test to measure data that satisfies and supports the objectives of the test. It refers to the extent of applicability of the concept to the real world instead of a experimental setup. With respect to psychometrics, it is known as test validity and can be described as the degree to which the evidence supports a given theory. It is important since it helps researchers determine which test to implement in order to develop a measure that is ethical, efficient, cost-effective, and one that truly probes and measures the construct in question. Other non-psychological forms of validity include experimental validity and diagnostic validity. Experimental validity refers to whether a test will be supported by statistical evidence and if the test or theory has any real-life application. Diagnostic validity, on the other hand, is in the context of clinical medicine, and refers to the validityof diagnostic and screening tests.

This statement is true because reliability and validity are two very different things. It is true that an assessment cannot be valid unless it is reliable. However, it can be reliable without being valid.

Reliability is a measure of whether an assessment will yield the same results at different times.

To better understand this relationship, let's step out of the world of testing and onto a bathroom scale.

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. However, if the scale is not working properly, this number may not be your actual weight. If that is the case, this is an example of a scale that is reliable, or consistent, but not valid. 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.

Switching back to testing, the situation is essentially the same. A test can be reliable, meaning that the test-takers will get the same score no matter when or where they take it, within reason of course. 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. However, a test cannot be valid unless it is reliable.