Professor Jamison is studying the impact of alcohol consumption on driving impairment. She divides participants into two groups. One group gets the treatment, in this case alcohol, and the other group does not. Participants then complete a task to measure their reaction time. Professor Jamison finds that those who had consumed alcohol had a slower reaction time than those who did not consume alcohol. She then concludes that alcohol consumption would impair driving ability. Why is she able to reach this conclusion