What hypothesis states that there is a statistically significant difference between two variables?

The alternative hypothesis serves to suggest that there is a statistically significant difference between two variables in a study. When researchers formulate their hypotheses, the alternative hypothesis provides a contrasting statement to the null hypothesis, which generally posits that there is no effect or no difference.

In hypothesis testing, the alternative hypothesis is often what the researcher aims to support. For example, if a study examines the effect of a new drug on blood pressure, the alternative hypothesis would assert that the drug does have an effect on blood pressure, indicating a difference between the treated group and a control group.

The other hypotheses mentioned do not propose a statistically significant difference. The null hypothesis maintains that there is no difference, the control hypothesis is not a standard term used in this context, and the research hypothesis, while similar, is typically synonymous with the alternative hypothesis but is less specifically defined in classic statistical terminology.