How does internal validity relate to external validity in research studies?

Understanding the relationship between internal and external validity is crucial in evaluating research studies. Internal validity refers to the degree to which a study accurately establishes a causal relationship between variables, ensuring that the results are due to the manipulation of the independent variable rather than other factors. On the other hand, external validity pertains to the extent to which the results of a study can be generalized to settings, populations, or times outside the experimental conditions.

The correct choice indicates that achieving high internal validity may indeed limit external validity. This situation often arises when a study is conducted under highly controlled conditions with a narrow and specific participant sample to minimize confounding variables. Such tightly controlled settings can produce very reliable and valid results but may not reflect real-world situations, thereby affecting how generalizable those findings are to other populations or contexts.

In contrast, the other options present misunderstandings about the dynamics of validity. The assertion that high internal validity guarantees high external validity inaccurately implies that the ability to draw causal conclusions directly translates into generalizability, which is not necessarily the case. The claim that internal validity focuses on participant diversity misrepresents its true focus, which is rather on the clarity of relationships between the variables of interest. Lastly, the statement about there being no relationship between internal and external