HELP PLEASE

Researchers are conducting clinical trials for a new medication to treat people suffering from asthma, a respiratory disease.
They selected 100 asthma patients from a national hospitals database in these age groups: under 15 years, 15 to 60 years,
and over 60 years. In each group, half the subjects received the new medication, and the other half received a placebo. The
subjects were not informed whether they received the medication or the placebo.
Which statements about this study are true?