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Xylitol is a food sweetener that may also have antibacterial properties, and researchers wanted to investigate whether regular use of a chewing gum containing xylitol would reduce middle ear infections for children in daycare. An experiment in Finland randomly divided 533 children in daycare centers into three groups. One group regularly chewed gum that contained xylitol, another group took xylitol lozenges, and the third group regularly chewed gum that did not contain xylitol. After 3 months, the researchers recorded whether or not each child had an ear infection during that period. Treatment by Ear Infection Count Yes No Expected Placebo Gum 49 129 178 39.4071 138.5929 Xylitol Gum 29 150 179 39.6285 139.3715 Xylitol 40 136 176 Lozenge 38.9644 137.0356 118 415 533Compute and interpret the estimated relative risk of a child getting an ear infection for those children who chew placebo gum compared to a child who chews xylitol gum. a The estimated relative risk is 1.70. Thus, children who chew the placebo gum are 1.70 times the risk of getting an ear infection compared to children who chew the xylitol gum. a The estimated relative risk is 1.70. Thus, children who chew the xylitol gum are 1.70 times the risk of getting an ear infection compared to children who chew the placebo gum. m The estimated relative risk is 0.86. Thus, children who chew the placebo gum are 0.86 times the risk of getting an ear infection compared to children who chew the xylitol gum. m The estimated relative risk is 1.16. Thus, children who chew the placebo gum are 0.86 times the risk to get an ear infection compared to children who chew the xylitol gum