Question

A Migraine is a particularly painful type of headache which patients sometimes wish to treat with acupuncture. To determine whether acupuncture relieves migraine pain, researchers conducted a randomized controlled study where 91 females diagnosed with migraine headaches were randomly assigned to two groups: treatment or control. 42 patients received acupuncture that is specifically designed to treat migraines. 49 patients in the control group received placebo acupuncture (needle insertion at nonacupoint locations). 24 hours after patients received acupuncture, they were asked if they were pain free. Results are summarized in the contingency table below. Pain Free Treatment 11 Control 1 Continued Pain_Total 42 49 31 Total 12 (a) What percent of patients in the treatment group were pain free 24 hours after receiving acupuncture? (Give each answer to the nearest tenth of a percent.) (b) What percent of patients in the control group were pain free after 24 hours? (Give each answer to the nearest tenth of a percent.) (c) Do the data suggest that acupuncture is more effective at migraine pain relief than a placebo? Ο Νο Yes (d) Select each of the following that are accurate statements: We need to know some probability to determine how likely it is that a difference in effectiveness this extreme could have occurred by chance. The data suggest that accupuncture is more effective than a placebo. The difference in effectiveness between acupuncture and placebo could not have happened by chance. The study would be more effective if patients could choose whether to be in the treatment group or the control group.