Does ginkgo improve memory? The law allows marketers of herbs and other natural substances to make health claims that are not supported by evidence. Brands of ginkgo
extract claim to ―improve memory and concentration.‖ A randomized comparative
experiment found no statistically significant evidence for such effects. The subjects were 230 healthy volunteers over 60 years old. They were randomly assigned to ginkgo or a placebo pill (a dummy pill that looks and tastes the same). All the subjects took a battery of tests for learning and memory before treatment started and again after six weeks.

Using the random digits below (starting at line 103), choose the first four members of the
ginkgo group. Explain your method.

103 45467 71709 77558 00095 32863 29485 82226 90056
104 52711 38889 93074 60227 40011 85848 48767 52573
105 95592 94007 69971 91481 60779 53791 17297 59335
106 68417 35013 15529 72765 85089 57067 50211 47487