Analyze each of the following investigations, or arguments, and indicate which of the methods of causal reasoning—Mill’s methods—are being used in each of them:

A simple, inexpensive and surprisingly powerful combination of treatments that all but wiped out malaria in a group of HIV-positive children in a recent study in Uganda was described at a very recent medical conference in Los Angeles. The combination—taking one inexpensive antibiotic pill each day and sleeping under an insecticide-treated mosquito net—reduced the incidence of malaria by 97 percent compared with a control group. The study, conducted by Dr. Anne Gasasira of Makerere University in Kampala, Uganda, found that among 561 healthy children who were not HIV-infected and who did not take the antibiotic or sleep under bed nets, there were 356 episodes of malaria. This compared with 4 episodes among 300 children who were known to be HIV-infected and received both treatments. “The findings were shockingly dramatic,” said Dr. Elaine Abrams, a professor of pediatrics and epidemiology at Columbia University.
—Reported at the 14th Conference on Retroviruses and Opportunistic Infections, Los Angeles, 28 February 2007