Inteal validity意思

"Internal validity" is a term used in research methodology, particularly in the social sciences, to describe the degree to which a study's design and implementation allow for the accurate determination of cause-and-effect relationships between variables. Internal validity is concerned with the extent to which the researcher can conclude that any observed changes or differences in the outcome variable are due to the manipulation of the independent variable (the cause) and not due to other factors.

In other words, internal validity is about ensuring that the results of a study are not the result of bias, confounding variables, or other sources of error. For example, if a researcher is studying the effect of a new drug on depression, they would want to ensure that any improvements in mood are due to the drug and not due to the placebo effect, the natural course of the disease, or other factors.

Internal validity is often contrasted with external validity, which is the extent to which the results of a study can be generalized to other populations, settings, and situations.