2. During the current influenza season, researchers want to know whether this year's influenza vaccine reduces the risk of contracting influenza. They recruited 100,000 adults from across Massachusetts and gathered data on whether they received the influenza vaccine. They then followed these adults for 8 months to determine how many developed influenza during the current season. A total of 46,800 participants received the influenza vaccine, and 4,860 of these adults had a positive influenza test. A total of 53,200 adults did not receive the influenza vaccination, 5,940 of which contracted influenza. a. What type of study are these researchers conducting? (1 point) b. Complete the following 2x2 table. (1 point) No Total Vaccine vaccine Influenza No influenza Total 100,000 c. What is an appropriate measure of association for determining if the influenza vaccine is associated with influenza risk? (1 point) d. Calculate the measure you named in (c). (2 points) e. Write a 1-2 sentence interpretation of your results. (2 points)4. A group of epidemiologists at Boston Children's Hospital wanted to investigate potential risk factors for autism. Using data from the World Health Organization, they calculated the average rate of MMR vaccination in a given set of countries with available data. Their results are shown in the following graph (articial data): '3' 30 7D '58 population with MMR vaccination D 10 20 3|] '0 Autism Incidence (per 10,000) a. What type of study design is this? (1 point) b. What hypothesis did the researchers likely generate from this data? (1 point) To further test their new hypothesis, the researchers designed a study in which they asked the parentslguardians of all patients attending their 12-month well-child visit within the Partners Healthcare System to participate in a longitudinal study evaluating childhood health outcomes in vaccinated children. (Note: in the US, the recommended vaccine schedule indicates the MMR vaccine be given at the 12-month well-child visit). 6. What type of study design is this? (1 point) (1. Name one limitation of the study design from 4c. (1 point) The result of their new study further supports their hypothesis that MMR vaccination is not associated with autism. However, during the course of their study, they had measured several other exposures for possible associations with autism and observed iron supplementation to be protective against autism. They now want to design a randomized controlled trial to further examine this association, specically focusing on newborn infants (