POP QUIZ !. Nominal, Ordinal or Continuous? 1.Temperature 2. GCS 3. Trauma Score.

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Presentation transcript:

POP QUIZ !

Nominal, Ordinal or Continuous? 1.Temperature 2. GCS 3. Trauma Score

Nominal, Ordinal or Continuous? 4. INH Stroke Scale 5. Apache Score 6. Probability of a disease

Nominal, Ordinal or Continuous? 7. Age 8. Sex 9. Visual Analog Pain Scale 10. Likert Scale

11.The Average is called the __________. 12.The Most Common value is called the ___________. 13.The Midpoint of the data is called the _________.

14.Which is most influenced by outliers? a. Mean b. Median c. Mode d. Average

15. A large Standard Deviation means there is a. a great deal of variability in the data b. little variability in the data c. a bimodal distribution d. equality between the mean, median and the mode.

16. A Small Standard Deviation means there is a. a great deal of variability in the data b. little variability in the data c. a bimodal distribution d. equality between the mean, median and the mode.

17. The Mean ± 1 S.D.encloses what % of the data? a. 50% b. 67% c. 75% d. 90% e. 95% f. 99%

18. The Mean ± 2 S.D.encloses what % of the data? a. 50% b. 67% c. 75% d. 90% e. 95% f. 99%

19. The Mean ± 3 S.D.encloses what % of the data? a. 50% b. 67% c. 75% d. 90% e. 95% f. 99%

20. What percent of Normal Persons will test Abnormal for any test? a. 0% b. 2.5% c. 5% d. 7.5% e. 10%

21. A BMP has 6 Independent Tests, What is the chance that all are “normal” if you are normal? A. 100% b. 95% c. 75% d. 50% e. 25%

22. Studies show that newer generation CT scanners are 95% sensitive for picking up subarachnoid bleeds on head CT scans. The concern that these scans may not be as sensitive for smaller subclinical bleeds is an example of: a. recall bias b. review bias c. spectrum bias d. intent to treat

23. The EKG is very specific in the diagnosis of acute myocardial ischemia. However, most studies use the EKG to define having had acute myocardial ischemia. This is: a. recall bias b. selection bias c. review bias d. spectrum bias

24. AIDS was first described in NYC and Los Angeles as two series of patients who presented to a clinic for an unusual skin tumor. a. case series b. randomized clinical trial c. case-control study d. cohort study e. cross-sectional study f. cross-over controlled clinical trial

25. A group of children are observed in a park. The activity level of the boys is compared to the activity level of the girls. The researcher notes if the child pretends it has a gun or not. a. case series b. randomized clinical trial c. case-control study d. cohort study e. cross-sectional study f. cross-over controlled clinical trial

26. A researcher examines the injuries received in auto accidents in a group of males who are intoxicated compared to another group that is not. a. case series b. randomized clinical trial c. case-control study d. cohort study e. cross-sectional study f. cross-over controlled clinical trial

27. A researcher follows two groups of males. One group consists of heavy drinkers, the other group uses no alcohol. The incidence of automobile wrecks is found for both groups at one and five years a. case series b. randomized clinical trial c. case-control study d. cohort study e. cross-sectional study f. cross-over controlled clinical trial

28. I think my patient has a 50% chance of having a stroke. a. The odds are.33 b. The odds are.5 c. The odds are 1 d. The odds are 5

Probability 29. Probability of 1% = Odds of ________ 30. Probability of 10% = Odds of ________ 31. Probability of 50% = Odds of ________ 32. Probability of 90% = Odds of ________

Odds 33. Odds of 0.01 = Probability of _________ 34. Odds of 0.1 = Probability of ________ 35. Odds of 1 = Probability of ________ 36. Odds of 9 = Probability of _______

a. True Positives b. True Negatives c. False Positives d. False Negatives 37.

38. Sensitivity is the a. True Positives over True negatives b.True Negatives over All with Disease c. True positives over All without disease d. True Positives over All with Disease e. True Positives over all who test positive

39. Specificity is the a. True Positives over true negatives b. True Negatives over All without Disease c. True positives over All with disease d. True Positives over All with Disease e. True Positives over all who test positive

40. Positive Predictive Value is the a. True Positives over true negatives b. True Negatives over All with Disease c. True positives over All without disease d. True Positives over All with Disease e. True Positives over all who test positive

41. Negative Predictive Value is the a. True Positives over true negatives b. True Negatives over All with Disease c. True positives over All without disease d. True Positives over All with Disease e. True Positives over all who test positive

42. Positive Likelihood Ratio = a. Sensitivity / Specificity b. Sensitivity / 1-Specificity c. 1-Sensitivity / Specificity d. Sensitivity x Specificity

43. Negative Likelihood Ratio = a. Sensitivity / Specificity b. Sensitivity / 1-Specificity c. 1-Sensitivity / Specificity d. Sensitivity x Specificity

44. The Chance of Disease After a Test is = A. Pretest Probability x LR b. Pretest Odds x LR c. Pretest Odds x Sensitivity d. Pretest Probability x Specificity

Answers

Nominal, Ordinal or Continuous? 1.Temperature (Continuous) 2. GCS (Ordinal) 3. Trauma Score (Ordinal)

Nominal, Ordinal or Continuous? 4. INH Stroke Scale (Ordinal) 5. Apache Score (Ordinal) 6. Probability of a disease (Continuous)

Nominal, Ordinal or Continuous? 7. Age (Continuous) 8. Sex(Nominal) 9. Visual Analog Pain Scale (Continuous) 10. Likert Scale (Ordinal)

11.The Average is called the _MEAN_________. 12.The Most Common value is called the __MODE_________. 13.The Midpoint of the data is called the __MEDIAN______.

14.Which is most influenced by outliers? a. Mean b. Median c. Mode d. Average

15. A large Standard Deviation means there is a. a great deal of variability in the data b. little variability in the data c. a bimodal distribution d. equality between the mean, median and the mode.

16. A Small Standard Deviation means there is a. a great deal of variability in the data b. little variability in the data c. a bimodal distribution d. equality between the mean, median and the mode.

17. The Mean ± 1 S.D.encloses what % of the data? a. 50% b. 67% c. 75% d. 90% e. 95% f. 99%

18. The Mean ± 2 S.D.encloses what % of the data? a. 50% b. 67% c. 75% d. 90% e. 95% f. 99%

19. The Mean ± 3 S.D.encloses what % of the data? a. 50% b. 67% c. 75% d. 90% e. 95% f. 99%

20. What percent of Normal Persons will test Abnormal for any test? a. 0% b. 2.5% c. 5% d. 7.5% e. 10%

u 21. A BMP has 6 Independent Tests, What is the chance that all are “normal” if you are normal? A. 100% b. 95% c. 75% =0.95 x 0.95 x 0.95 x 0.95 x 0.95 x 0.95 d. 50% e. 25%

22. Studies show that newer generation CT scanners are 95% sensitive for picking up subarachnoid bleeds on head CT scans. The concern that these scans may not be as sensitive for smaller subclinical bleeds is an example of: a. recall bias b. review bias c. spectrum bias d. intent to treat

23. The EKG is very specific in the diagnosis of acute myocardial ischemia. However, most studies use the EKG to define having had acute myocardial ischemia. This is: a. recall bias b. selection bias c. review bias d. spectrum bias

24. AIDS was first described in NYC and Los Angeles as two series of patients who presented to a clinic for an unusual skin tumor. a. case series b. randomized clinical trial c. case-control study d. cohort study e. cross-sectional study f. cross-over controlled clinical trial

25. A group of children are observed in a park. The activity level of the boys is compared to the activity level of the girls. The researcher notes if the child pretends it has a gun or not. a. case series b. randomized clinical trial c. case-control study d. cohort study e. cross-sectional study f. cross-over controlled clinical trial

26. A researcher examines the injuries received in auto accidents in a group of males who are intoxicated compared to another group that is not. a. case series b. randomized clinical trial c. case-control study d. cohort study e. cross-sectional study f. cross-over controlled clinical trial

27. A researcher follows two groups of males. One group consists of heavy drinkers, the other group uses no alcohol. The incidence of automobile wrecks is found for both groups at one and five years a. case series b. randomized clinical trial c. case-control study d. cohort study e. cross-sectional study f. cross-over controlled clinical trial

28. I think my patient has a 50% chance of having a stroke. a. The odds are.33 b. The odds are.5 c. The odds are 1 d. The odds are 5

Probability 29. Probability of 1% = Odds of __0.01___ 30. Probability of 10% = Odds of __0.11__ 31. Probability of 50% = Odds of __1__ 32. Probability of 90% = Odds of _9__

Odds 33. Odds of 0.01 = Probability of __1%__ 34. Odds of 0.1 = Probability of __10%___ 35. Odds of 1 = Probability of ___50%___ 36. Odds of 9 = Probability of __90%__

a. True Positives b. True Negatives c. False Positives d. False Negatives 37.

38. Sensitivity is the a. True Positives over True negatives b.True Negatives over All with Disease c. True Positives over All without disease d. True Positives over All with Disease e. True Positives over all who test positive

39. Specificity is the a. True Positives over true negatives b. True Negatives over All without Disease c. True positives over All with disease d. True Positives over All with Disease e. True Positives over all who test positive

40. Positive Predictive Value is the a. True Positives over true negatives b. True Negatives over All with Disease c. True positives over All without disease d. True Positives over All with Disease e. True Positives over all who test positive

41. Negative Predictive Value is the a. True Positives over true negatives b. True Negatives over All with Disease c. True Positives over All without disease d. True Positives over All with Disease e. True Positives over all who test positive

42. Positive Likelihood Ratio = a. Sensitivity / Specificity b. Sensitivity / 1-Specificity c. 1-Sensitivity / Specificity d. Sensitivity x Specificity

43. Negative Likelihood Ratio = a. Sensitivity / Specificity b. Sensitivity / 1-Specificity c. 1-Sensitivity / Specificity d. Sensitivity x Specificity

44. The Chance of Disease After a Test is = A. Pretest Probability x LR b. Pretest Odds x LR c. Pretest Odds x Sensitivity d. Pretest Probability x Specificity