What are the source and study populations for this study 2 What are \u012e \u0215 \u0216 and \u012f

What are the source and study populations for this

This preview shows page 217 - 220 out of 550 pages.

1.What are the source and study populations for this study? 2.What are Į, ȕ, Ȗ, and įfor this study? 3.Are Į, ȕ, Ȗ, and įselection probabilities? 4.Why is there selection bias in the odds ratio estimate? Explain in terms of selection ratios. 5.What is the direction of the bias? 6.Why is this an illustration of Berkson’s bias?
Selection Bias Community Population Smoke? Disease Yes No Total Yes 400 200 600 No 100,000 200,000 300,000 Total 100,400 200,200 300,600 Hospital Case-Control Sample Smoke? Yes No Total Case 225 75 300 Control 150 150 300 Total 375 225 600 7.Are the controls in the above study over-representative of the non-cases in the community? 8.What are Į, ȕ, Ȗ, and įfor this study? 9.In terms of selection probabilities, why is there selection bias in the odds ratio estimate? 10.What is the direction of the bias? 11.Why is this an illustration of Berkson’s bias?
Image of page 220

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture