For RD exam video lectures & colorful notes, check out https://www.chompdowndietetics.com/ For practice questions, follow @rdexampodcast on Instagram and FaceBook Today's episode covers vitamin D pathways, randomized clinical trials, and parallel vs crossover designs.  1. What is the name for the active form of vitamin D? A. CholecalciferolB. 7-dehydrocholesterolC. Calcitriol D. Calcidiol 2. Which of the following is an example of an RCT? A. A study consists of two groups, A and B. Group a consisted of participants who had been smoking for 10 or more years. Group B consisted of participants who had never smoked. Both groups were followed for 10 years to see if they develop COPD. B. A study consists of two groups, A and B. Group a consisted of participants who had liver disease. Group B consisted of participants who did not have liver disease. Both groups were compared to see what proportion of them had been consuming alcohol on a regular basis for ten years C. A study examining the effects of a cholesterol drug randomly placed participants into two groups, a and b. Group a received the cholesterol drug whereas group b received a placebo. D. None of the studies mentioned are an example of an RCT   3. A study consisted of three groups. Participants were randomly assigned to groups in which they stayed throughout the study. Group A received treatment A. Group B received treatment B. Group C received a placebo. Which of the following best describes what type of design this study is an example of? A. Randomized Clinical Trial Crossover study B. Randomized Clinical Trial Parallel study C. Randomized Clinical Trial D. All of the above