What is Validity in Psychology [Updated 2024]

What is Validity in Psychology - Validity in Psychology - When designing and using tests and other methods of assessing people, it is important that the test and its use is valid.

Definition of Validity in Psychology | Validity in Psychology Definition

Validity of a test refers to the degree to which a test measures and what it purpose to measured. Frank. S Freeman

Validity Psychology Definition - The validity of a test is defined as the extent to which the test measures, what it design to measure. Aiken Psychological Testing and Assessment

Validity vs Reliability or Reliability vs Validity in Psychology

Validity vs Reliability - Reliability is the necessary condition but not a sufficient condition for validity. Validity is based on empirical evidence.

Validity of Psychological Test or What is Validity in Psychology?

What is Validity in Psychology - Validity has been described as 'the agreement between a test score or measure and the quality it is believed to measure (Kaplan and Saccuzzo, 2001).

In other words validity in psychology, it measures the gap between what a test actually measures and what it is intended to measure.
This gap can be caused by two particular circumstances:

• The design of the test is insufficient for the intended purpose. 
• The test is used in a context or fashion which was not intended in the design.

In science and statistics, validity in psychology has no single agreed definition but generally refers to the extent to which a concept, conclusion or measurement is well-founded and corresponds accurately to the real world.

The word "valid" is derived from the Latin validus, meaning strong.

In psychometric, validity in research has a particular application known as test validity: "the degree to which evidence and theory support the interpretations of test scores" ("as entailed by proposed uses of tests").

Similarly in the area of scientific research design and experimentation, validity refers to whether a study is able to scientifically answer the questions it is intended to answer.

For clinical fields, the validity of a diagnosis and associated diagnostic tests may be assessed.

Scientific Validity in Research

It is generally accepted that the concept of scientific validity addresses the nature of reality. And as such is an epistemological and philosophical issue as well as a question of measurement. The use of the term in logic is narrower, relating to the truth of inferences made from premises.

Validity in Psychology - Validity the best available approximation to the truth of a given proposition, inference, or conclusion.

The first thing we have to ask is: "validity of what?"

When we think about validity in research, most of us think about research components. We might say that a measure is a valid one, or that a valid sample was drawn, or that the design had strong validity. But all of those statements are technically incorrect.

Measures, samples and designs don't 'have' validity, only propositions can be said to be valid. Technically, we should say that a measure leads to valid conclusions or that a sample enables valid inferences, and so on. It is a proposition, inference or conclusion that can 'have' validity.

What is Validity in Psychology - We make lots of different inferences or conclusions while conducting research. Many of these are related to the process of doing research and are not the major hypotheses of the study. 

Validity in Psychology - Nevertheless, like the bricks that go into building a wall, these intermediate process and methodological propositions provide the foundation for the substantive conclusions that we wish to address. 

For instance, virtually all social research involves measurement or observation. And, we are concerned with whether we are measuring, what we intend to measure or with how our observations are influenced by the circumstances in which they are made.

We reach conclusions about the quality of our measures, conclusions that will play an important role in addressing the broader substantive issues of our study.

When we talk about the validity of research, we are often referring to these to the many conclusions we reach about the quality of different parts of our research methodology.

We subdivide validity in psychology into four types. Each type addresses a specific methodological question. In order to understand the types of validity, you have to know something about how we investigate a research question. 

Because all four validity types are really only operative when studying causal questions, we will use a causal study to set the context.

There are really two realms that are involved in research or validity in research.

The first, on the top, is the land of theory. It is what goes on inside our heads as researchers. It is where we keep our theories about how the world operates.

The second, on the bottom, is the land of observations. It is the real world into which we translate our ideas -- our programs, treatments, measures and observations.

Validity in Psychology - When we conduct research, we are continually flitting back and forth between these two realms, between what we think about the world and what is going on in it.

Cause and Effect Relationship or What is Cause and Effect Relationship?

Cause and Effect Relationship - When we are investigating a cause and effect relationship, we have a theory (implicit or otherwise) of what the cause is (the cause construct). 

For instance, if we are testing a new educational program, we have an idea of what it would look like ideally. 

Similarly, on the effect side, we have an idea of what we are ideally trying to affect and measure (the effect construct).

But each of these, the cause and effect, has to be translated into real things, into a program or treatment and a measure or observational method.

We use the term operationalization to describe the act of translating a construct into its manifestation. In effect, we take our idea and describe it as a series of operations or procedures. Now, instead of it only being an idea in our minds, it becomes a public entity that anyone can look at and examine for themselves.

Conclusion

It is one thing, for instance, for you to say that you would like to measure self-esteem (a construct). But when you show a ten-item paper-and-pencil self-esteem measure that you developed for that purpose, others can look at it and understand more clearly what you intend by the term self-esteem.

Types of Validity in Psychology