The following is an excerpt from "The Oregon Experiment- Effects of Medicaid on Clinical Outcomes," by Baicker et al. (2013). Fill in the blank identifying the method used in this paper given the description in the paragraph (I've given you a hint on the key points by italicizing a few phrases): "Adults randomly selected in the lottery were given the option to apply for Medicaid, but not all persons selected by the lottery enrolled in Medicaid (either because they did not apply or because they were deemed ineligible). Lottery selection increased the probability of Medicaid coverage during our study period by 24.1 percentage points (95% confidence interval [CI], 22.3 to 25.9; P