Objectives
to Study
Role
Study
Study
Questions
| Learning Objectives |
> | Introduction to Study |
> | Student Role |
> | Dr Stellman's Study |
> | Dr Shapiro's Study |
> | Discussion Questions |
|
| 1. | Suppose that you were told that the clinical setting from which researchers got their cases and controls was a tertiary care facility, which is a specialized hospital equipped with diagnostic and treatment facilities to treat bladder cancer. What type of bias might be introduced in the selection of controls and why? Please, note that different tertiary care facilities may be specialized to treat different diseases and therefore people may travel from far away places to get to the facility. They may also be admitted to it simply because they happen to live nearby. | ||
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a. | selection bias | |
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b. | recall bias | |
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c. | surveillance bias | |
Hypothetical selection of cases and controls for the hospital-based case-control study to show selection procedures and their effects.
[ Open Exercise in New Window ]
| 2. | Which situation do you think is the best: | ||
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a. | situation 1 | |
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b. | situation 2 | |
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c. | situation 3 | |
| 3. | If the researchers had a choice of how and where they could obtain subjects with bladder cancer, what do you think would be the best source for the cases? | ||
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a. | hospital | |
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b. | tumor registry | |
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c. | death certificates | |
Intellectually curious? Learn more about tumor registries.
| 4. | What potential problem could have been introduced if you found out that interviews with cases took 30 minutes longer than interviews with controls? | ||
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a. | selection bias | |
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b. | information bias | |
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c. | volunteer bias | |
| 5. | In the study of artificial sweetener use and bladder cancer, authors collected information regarding artificial sweetener use and diet beverages. The duration of artificial sweetener use and or diet beverage differed for both cases and controls. For instance, some persons consumed these products as far back as 10 years ago whereas others continued to consume these products during the time that the study was conducted. What potential problems could arise when trying to measure exposures that happened over different time periods? | ||
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a. | Misclassification | |
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b. | Reporting bias | |
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c. | Surveillance bias | |
| 6. | What would have happened if interviewers were aware of the disease status of the study subjects? | ||
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a. | It would have benefited the study as the interviewers would have collected better data. | |
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b. | It would not change the results of the study. | |
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c. | It would irreparably damage the data by introducing the interviewer bias. | |
| Learning Objectives |
> | Introduction to Study |
> | Student Role |
> | Dr Stellman's Study |
> | Dr Shapiro's Study |
> | Discussion Questions |
|
