Question

2. For the following observational studies, indicate whether they are prospective or retrospective studies. a) An airline was concerned that new security measures might discourage air travelers. A year after the new security restric- tions were put into place, the airlines compared the miles traveled by their frequent fliers before and after the change. b) Does giving children a flu shot protect parents? Re- searchers questioned a random sample of families at the end of a flu season. They asked whether the children had been immunized, whether the parents had received flu shots, and who in the family had contracted the flu

Answer 1