Experimental validity
Experimental validity (validity of an experiment) is a measure of how sound and properly conducted an experiment is, as well as how well supported the conclusions drawn from its results are.
In experimental psychology, several types of experimental validity are distinguished:
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Internal validity (internal validity): This form of validity assesses the extent to which the results of an experiment can truly be attributed to the effect of the independent variable rather than to other factors. Internal validity requires the experiment to control the influence of extraneous variables and isolate the effect being studied.
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External validity (external validity): This type of validity assesses the extent to which the results of an experiment can be generalized to a broader population or other contexts. External validity indicates how well experimental results reflect real-world situations or conditions.
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Operational validity (operational validity): This aspect assesses how effectively the variables used in the experiment are defined and measured. Operational validity concerns the appropriateness of the selected measurement methods and the operationalization of concepts.
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Construct validity (construct validity): This type of validity assesses how accurately and adequately the experimental variables and procedures represent and measure the specific psychological construct or concept that the researcher is attempting to study.
The level of experimental validity depends on how carefully the researcher designs and conducts the experiment, as well as how effectively potential biases and extraneous factors are controlled.