Which of the following criteria is NOT required for a causal claim?

In the context of making causal claims in research, covariance, temporal precedence, and internal validity are all essential criteria that must be established.

Covariance refers to the relationship between two variables, indicating that changes in one variable are associated with changes in another. Without establishing that there is a relationship, claiming a causal link would not be valid.

Temporal precedence is crucial because it determines the direction of the causal relationship, showing that one variable occurs before the other. This is necessary to argue that one variable causes changes in another.

Internal validity ensures that the effects observed in an experiment can be attributed to the manipulation of the independent variable, rather than to other confounding factors. Establishing internal validity strengthens the argument that causal relationships are genuinely reflective of the experimental design.

External validity, while important in discussing the generalizability of findings beyond the study sample, does not directly impact the ability to make a causal claim within the study itself. Therefore, it is not a required criterion for establishing a causal relationship in the context of the specific research. This makes it the correct choice in the question asked.