Chapter 10: Data Interpretation Issues Flashcards
What is validity of study?
the degree to which the inference drawn from a study is warranted when account is taken of the study methods, the representativeness of the study
- internal validity: affected by design of study itself
- external validity: affects generalizability of results
Internal validity?
Deals w/ things or people who have participated in the exact study
External validity?
Applies to things or people outside of the study
What are types of error?
- Random error
- Systematic error (bias)
Random error?
Reflect fluctuations around a true value of a parameter (such as a rate or relative risk) due to sampling variability
Systematic error?
Refers to measurement related biases/issues
Types of bias?
- Selection
- Information
- Confounding
Selection bias?
Issues surrounding recruitment and retention of subjects
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Information bias?
Measurement or classification error
-Recall bias
Confounding bias?
Interpretation error by failing to account for a 3rd variable (or another factor apart from exposure and disease)
Ex: when researchers think an increase drinking coffee causes more people to get lung cancer. However, there has to be an extra factor at cause. In this case, that would be cigarette smoking
What is sensitivity?
The ability of a test to correctly identify those with a condition
What is specificity?
The ability of a test to correctly identify those without a condition
Misclassification?
Errors in classifying disease or exposure status
Differential misclassification?
– Errors in measurement differ by comparison group
– Yields invalid results
Non-differential (random) misclassification?
– Errors in assignment happen equally for both study groups
– Tends to dilute findings
