Early exposure to complex dietary proteins may increase risk of Type 1 diabetes in children with genetic susceptibility to this disease. In a double-blind randomized clinical trial reported in JAMA infants identified to be genetically at risk for developing Type 1 diabetes, were randomly assigned to a conventional formula group or a hydrolyzed formula group after weaning (Writing Group for the TRIGR Study Group 2018). Conventional formula contains proteins while hydrolyzed formula contains no intact proteins. Of the 1079 infants in the conventional formula group, 82 developed the disease by age 11.5 years. Of the 1983 infants assigned to the hydrolyzed formula group, 91 developed the disease by that age.

a. Identify the treatment and response variables.

b. Test the hypothesis that type of formula and development of Type 1 diabetes are independent using a significance level of 0.05.

c. Based on this study, do you think dietary recommendations for infants at risk for Type 1 diabetes should be revised to recommend hydrolyzed formula over conventional formula? Explain.