Question: Asthma is a reemerging health problem among children. In one experiment, a group whose attacks began before age 3 was compared with a group whose attacks began later (Mrazek, Schuman, and Klinnert, 1998). The dependent variable was the child's score on the Behavioral Screening Questionnaire (BSQ), which was filled out by the mother. High BSQ scores indicate more problems. Analyze the difference between means and write a conclusion.

                    Onset of asthma

          Before age 3           After age 6

X¯          60                          36

s^{^}          12                           6                         

N           45                          45