Question

The Following True/False Questions are worth 1 point each 15)Length time bias makes it seem as though people live longer if they are screened 16) Equipoise is when there is real uncertainty regarding which treatment arm is the most beneficial for the trial participants. 17)Often, a carry-over effect in a cross over trial can be ameliorated (made less severe) by extending the washout 18)It is difficult to develop a flu vaccine because the virus 19)Race is a socially constructed concept that changes by 20Case Control Studies are best for rare exposures. period mutates often and there are many different strands. place and time. 21)_Selection bias is a huge concern only with cross sectional study designs. 22)Ecological Studies are never used because of the ecological fallacy, where an association observed among groups is applied at the individual level 23)__The following is a graph of a propagated epidemic Cases of Measles by Date of Onset 35 30 25 20 15 10 5 Successively Larger Peaks Index Case 11 15 19 23 27 31 4 8 12 16 20 2428 2 6 10 14 18 22 2630 3 7 March April May June Date of Onset

Answer 1

ANSWER

15 .TRUE. Length time bias make it seems as through people

       live longer if they are screened.

16.TRUE. Equipoise when there is a real uncertainity regarding

      which treatment arm is the most beneficial for the participants.

17.TRUE. Often carry over effect in a cross over trial can be ameliorated

     by extending the washout period.

18.TRUE. It is difficult to obtain flu vaccine because the virus mutate often

     and there are multiple strands.

19. TRUE.Race is a socially constructed concept which changes over time

      and place.

20. TRUE. Case control studies are best for rare explosure.

21.TRUE. Selection bias is a huge concern only with cross sectional study

      designs.

22.TRUE. Ecological studies are never used because of the ecological fallocy

      where an association observed among groups is applied at the individual

      level.

23.TRUE, Above graph shows a propagated epidemic.