(a) Which of the three tests is the most appropriate, and why? Clearly state your reasoning. (b) For the analysis selected in (a) above, write a conclusion in the style of a research report. Marks will be awarded for being clear and concise.WORKSHEET 1 Two-Sample T-Test and Cl: Placebo, Lavage Method That population mean of Placebo wy population mean of Lavage Differences Hy - wa Equal variances are assumed for this analysis. Estimation for Difference 95% Cl for Difference Pooled StDev Difference -5.09 19.28 (-12 06, 1.86) Test Null hypothesis Alternative hypothesis Hip - ki # 0 T-Value OF P-Value -1.45 118 0.151 WORKSHEET 1 Paired T-Test and Cl: Placebo, Lavage Estimation for Paired Difference 95% Cl for Mean StDev SE Mean u difference -5.09 26.24 3.39 (-11.87, 1.69) It_ difference population mean of (Placebo - Lavage) Test Null hypothesis He u_difference = 0 Alternative hypothesis Hit u_difference # 0 T-Value P-Value -1.50 0.138Question 17 (5 marks) (2 + 3 = 5 marks) J.B. Moseley et al. (2002) were studying whether laparoscopic lavage (a form of knee surgery) was effective. They compared this to placebo knee surgery (where a cut was made, but the laparoscopy was not inserted). A total of 120 individuals with osteoarthritis of the knee were randomly assigned to the two treatments, and the data collected were KSPS scores (a measure- ment of knee pain, higher values indicate more pain). Some alternative analyses on these data were performed: WORKSHEET 1 Two-Sample T-Test and Cl: Placebo, Lavage Method Hit population mean of Placebo was population mean of Lavage Difference: His = Wa Equal variances are not assumes for thi anglais. Descriptive Statistics Sample N Mean StDev SE Mean Placebo 60 46.7 21.5 2.8 Lavage 60 51.8 168 2.2 Estimation for Difference 95% Cl for Difference Difference -5.09 (-12.07, 1.89) Test Null hypothesis Alternative hypothesis Hips . ke . 0 T-Value OF P-Value -1.45 111 0.151