Health Science Midterm #2

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Health Science Midterm #2
2013-10-28 01:00:42
chapter 13

Health Science
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  1. What is random error?
    A divergence, due to chance alone, of an observation on a sample from the true population value.
  2. What does error lead to?
    imprecise results
  3. Define precision.
    • little variation between the results
  4. What is sampling error?
    occurs as a part of the processes of selecting study participants
  5. What are the 6 steps to health research?
    • 1. define a question
    • 2. sample
    • 3. measure
    • 4. intervene
    • 5. describe/analyze relationships
    • 6. make inferences
  6. Define Inference.
    Applying observations of study sample to the entire source population
  7. What is systematic error? (2)
    • error resulting from flaw either in the method of selection of study participants or in the procedures for gathering relevant exposure and/or disease information
    • affects every singe participants data
  8. Define validity.
    The degree to which measurement measures what is meant purports to measure
  9. Why is it good to survey a larger sample size?
    It better represents the population
  10. As sample size INCREASES, Random error __________.
  11. What is significant about systematic error aka Bias? (3)
    • results tend away from the truth systematically
    • cannot be addressed with analysis
    • flaw in study design
  12. Error can affect the _______ and ________ of results.
    • accuracy
    • precision
  13. Define accuracy.
    when observed result is close to the truth value
  14. precision results in?
    low random error
  15. accuracy results in?
    low systematic error
  16. True or False. The greater our sample size, the less likely we are to see systematic error. (2)
    • False, happens in the outset
    • error happens to every participants data
  17. What is selection bias?
    occurs when there is a systematic difference between the characteristics of people selected for a study and the characteristics of those who are not.
  18. What is selection bias categorized into?
    systematic error in selecting study participants
  19. What are the selection bias in cross sectional studies?
    • survivor bias
    • volunteer bias
  20. Define survivor bias. (2)
    • aka incidence/prevalence
    • when survivors being surveyed or studied are not representative of the entire diseased population