HP3 Quiz 3 Practice

21

Multiple Regression Analysis

With regards multiple regression analysis, which of the following statements is/are correct?


22

Table 2 - Multiple Logistic Regression analysis for CAD:



With regards Table 2, which of the following statements is/are correct?


23

With regards Table 2, what is the p value of the adjusted odds ratio for female sex likely to be and why?


24

Clinical Trial Profile and Loss to Follow-up

Questions 24 to 26 inclusive are related to the following information and Figure 7.

The trial profile in Figure 7 comes form a randomised controlled trial of compression stockings vs no stockings for prevention of symptomless DVT in long-haul flights. (Scurr et al. The Lancet 2001;357:1485)

Figure 7 - Trial profile:



With regards the Trial Profile (Figure 7), which of the following statements is/are correct?


25

There were 12 DVTs in the control group and no DVTs in the stocking group. In a worst case scenario analysis performed in order to quantify the potential impact of loss to follow-up on the findings of the study, what would be the incidence rate of DVT in each group?


26

Regarding an intent-to-treat (ITT) analysis, which of the following statements is/are correct?


27

Survival Analysis

The information below and Figure 8 relate to questions 27 to 30.

A randomised controlled trial was undertaken to compare the efficacy and safety of open versus endovascular repair of abdominal aortic aneurysm. Kaplan Meier (K-M) survival analysis on an intention-to-treat basis was undertaken to compare outcomes in the two groups. For the outcome ‘survival free of severe events’ K-M survival curves for the two groups are presented in Figure 8.

Figure 8:



At the commencement of the study, how many patients were randomly assigned to each of the open and endovascular repair groups?


28

After 12 months of follow-up, what was the cumulative probability of survival in the open repair group?


29

At each time point, what constitutes the ‘number at risk’ in each group?


30

Which of the following statements is/are correct?