**Core Concept**
Establishing causality in epidemiological studies is crucial for understanding the relationship between risk factors and diseases. The Bradford Hill criteria, a set of nine principles, are used to evaluate the strength of associations between potential causes and effects.

**Why the Correct Answer is Right**
The Bradford Hill criteria provide a framework for assessing causality in epidemiological studies. The criteria include aspects such as strength of association, consistency of findings, and temporality of the relationship. These criteria help researchers to evaluate the likelihood of a causal relationship between a potential cause and an effect. The correct answer is the criterion that is most relevant to establishing temporality, which is a critical aspect of causality.

**Why Each Wrong Option is Incorrect**
**Option A:** Temporality is not the first criterion listed in the Bradford Hill criteria. The criteria are:
- Strength of association
- Consistency of findings
- Specificity of the association
- Temporality
- Biological gradient (dose-response relationship)
- Plausibility
- Coherence
- Experiment
- Analogy

**Option B:** The Bradford Hill criteria are not primarily concerned with the statistical significance of an association. While statistical significance can provide evidence for an association, it is not a direct measure of causality.

**Option C:** The Bradford Hill criteria are not a set of statistical tests. They are a framework for evaluating the strength of evidence for causality in epidemiological studies.

**Option D:** The Bradford Hill criteria are not a set of principles that are used to evaluate the effectiveness of interventions. They are used to evaluate the strength of associations between potential causes and effects.

**Clinical Pearl / High-Yield Fact**
When evaluating the causality of an association in epidemiological studies, it is essential to consider multiple criteria, including temporality, strength of association, and consistency of findings. By doing so, researchers can increase the confidence in their conclusions and reduce the risk of false positives.

**Correct Answer: D. Temporality**