D\'s Epidemi & Ethics

  1. Gold standard for testing therapies
    Randomized Clinical Trial

    • Double Blinded
    • Randomized
  2. Examines group exposed to given situation or factor. Prospective or retrospective study.
  3. Cohort study conclusions
    Relative risk
  4. Retrospective comparison of pts with disease with healthy controls, frequency of certain exposures in both groups is considered
    Case Control
  5. Case control conclusions
    Odds ratio
  6. Survey of large number of people at one time to assess exposure and disease prevalence
    Cross sectional
  7. Cross sectional conclusions
    • Hypothesis for risk factors
    • Disease prevalence
  8. Report of characteristics of a disease by examining multiple cases
    Case Series
  9. Case Series conclusions
    Hypothesis for risk factors
  10. Pooling of multiple studies examining a given disease or exposure
  11. What study can examine rare exposures and study multiple effects of exposure
    Cohort Study
  12. Study that can examine rare dz or those with long course in short amount of time
    Case control
  13. Can study multiple typed of exposure and may examine small group size.
    Case Control
  14. Study that can be used to estimate disease prevalence following exposure
    Cross Sectional
  15. Larger study size that can resolve conflicts in literature.
  16. What study is susceptible to recall bias?
    Case Control
  17. Study Susceptible to selection bias?
    Case control
  18. Name the bias: nonrandom assignment of subjects to study groups
    Selection/Enrollment Bias
  19. Subjective interpretation of data by investigator deviates toward desired conclusions
  20. Name the bias: Screening test provides earlier diagnosis in studied group compared to controlled, but has no effect on time of survival.
    Lead Time Bias
  21. Name the bias: screening test detects several slowly progressive cases of a disease & misses rapidly progressive cases.
    Lenth Bias
  22. Name the bias: subjects may respond to subjective q's in a different way than normal bc awareness of study changes their perception of examined issue
    Observational Bias
  23. Studies showing a difference b/t groups more like to be published than studies that don't show a difference.
    Publication bias
  24. Name the bias: errors of memory within subject bc of prior confounding experiences
    Recall Bias
  25. Pts with a certain medical hx may be more likely to participate in a study related to their condition
    Self selection bias
  26. Consequence of selection bias
    Results not applicable to general population
  27. Consequence of investigator bias
    Results of study incorrectly resemble proposed hypothesis
  28. Consequence of lead time bias:
    Time from diagnosis to outcone increases to cause a false appearance of increased time of survival.

    Time from dz occurence to outcome actually remains tge same regardless of screening
  29. Consequence of length bias
    Effectiveness of screening test overstated
  30. Consequence of observational bias
    Effectiveness of therapy not accurately depicted in study group
  31. Consequence of publication bias
    Dats available for meta-analysis may not include studies that support the null hypothesis
  32. Consequence of recall bias
    Pt with negative experiences are more likely to recall negative details
  33. Consequence of self selection
    Subjects are not representative of the general population & introduce confounding variables
  34. How do u avoid investigator and observational bias?
    Double blind a study
  35. Dz with  prevalence will e associated with
     Positive predictive value in a screening test
  36. Dz with  prevalence will be associated with
     Negative predictive value in a screeninh test
  37. Null hypothesis
    States no association exists between exposure and disease (or treatment and response)
  38. Type I error
    Null hypothesis is rejected even though its true

    (False Positive)
  39. Type II error
    Null hypothesis is not rejected even though it is false

    (False Negative)
  40. Risk of type 1 & 2 errors decrease by?
    Increasing Sample Size

    (increasing power)
Card Set
D\'s Epidemi & Ethics
Epidemi & Ethics