200 subjects, all with common colds, participate in a trial fora new cough medicine. 100 subjects are randomly placed in thetreatment group, while the other 100 are placed in the controlgroup and given a placebo. A short while later, evaluators (whoaren’t told which group each subject was in until after theirevaluation) determine that 45% of subjects in the treatment groupare coughing less, compared to 36% of subjects from the control. Isthe medicine effective?
