A study was conducted to Investigate which intervention is most efficacious (effective) in reducing obesity in children. Three Interventions were tested: (1) Routine clinical care (control), (2) Physical activity and dietary instruction provided during 8 weekly visits, and (3) Physical activity and dietary instruction provided via 8 weekly interactive modules. A total of 300 children were recruited into the study and randomized in blocks of 9 to receive one of the three interventions. The primary outcome was the change in body mass index (BMI) after & weeks of the intervention (baseline vs, week 8), In this study, BMI was heavily skewed left. 1a. What is the study design? * ecological study * retrospective cohort study * cross-sectional study * case-control study randomized clinical trial 1b. What are the null and alternative hypotheses? • Ho: M1 = M2 = M3 = M vs. H1: At least two medians differ O Ha: M1 = M2 = M3 = M vs. Ho: At least two medians differ • H0 u1 = M2 = M3 -= H4 vs. HA at least two means differ 0 HA1 = 12 = 13 = 44 vs. HO at least two means differ • Ho: M1 = M2 = M3 = M4 vs. H1: No medians are equal 1c. What type of statistical test would you use to analyze this data? * Independent t-test * Kruskal-Wallis * Paired t-test * One-way ANOVA * Friedman-Kendall-Smith * Wilcoxon rank sum test 1d. Why (provide at least two reasons)? An investigator was interested in how beliefs and attitudes about treating incarcerated people change after increasing exposure to treating inmates during the course of their medical training. A survey was administered to 500 first year medical students prior to exposure treating inmates, and then again at graduation, after they had experience treating the incarcerated. The survey consisted of 20 likert-scale questions (range from strongly disagree to strongly agree) and a summary score was calculated (100 points total) and was found to be normally distributed. The investigators hypothesize that medical students’ scores will increase from year 1 to year 4, as higher scores predict more sympathetic responses to inmates. 2a. What is the study design? (prospective) cohort study cross-sectional study randomized clinical trial retrospective cohort study case-control study 2b. What are the null and alternative hypotheses? HO: Md ≤0 vs. HA: Ma > 0 * HO: 11 ≤ M2 VS. HA: 41 > M2 * HO: Md = 0 vs. HA: Ma > 0 * HO: M1 = H2 VS. HA: M1 $ 12 * HO: p = 0 vs. HA: p $ 0 2c. What type of statistical test would you use to analyze this data? paired t-test * independent t-test * t-test for one sample * Pearson's Chi-square * McNemar's chi-square 2d. Why (provide at least two reasons)? A study was conducted to investigate possible risk factors for poor outcomes after a total shoulder replacement. Three different brands of implants were used to perform the surgery and the investigator wants to know which of the three implants is associated with having a higher complication rate. Patients were followed for 2 months post-surgery to determine if a complication has occurred. For the primary outcome, the researchers used several factors to define “poor outcome,” including infection and the need for repeat surgery (poor outcome: yes/no). 3a. What was the study design? Nested Case-Control Study Randomized Clinical Trial (RCT) cohort study Cross-sectional Study Case-Control Study Case Report 3b. What are the null and alternative hypotheses? • HO: M1 = M2 = M3 = M vs. H1: At least two medians differ • HO: ud 0 vs. HA: ud > 0 • Ho: M = 0 vs. HA: M + 0 • Ho: 1 - 42 vS. HA: M1 > 42 Question 11 3c. What type of statistical test would you use to analyze the data? * Pearson's Chi-square * Independent t-test * McNemar's chi-square Fisher's Exact Test RxC Chi-square