Compute questions 1- 3 using the order of operations.
1. (5-3)!/6 x (14 + 8/2)
2. 7 x ((11 - 6) - 32)
3. ((8 - 5)!2 + 24/3
An investigator wants to evaluate the relationship between diabetes type II and several health indicator variables. The investigator has identified 75 patients diagnosed with type II diabetes and 75 patients who are the same sex and age group but do not have diabetes. The investigator then questions each of the patients about their past eating habits, their current height and weight to calculate their BMI, as well as their family history of diabetes.
4. What type of study does the above scenario describe?
a. Case-Series
b. Prospective Cohort
c. Case-Control
d. Retrospective Cohort
5. The investigator asks them to specify how much added sugar they intake on a daily basis by using the following categories: minimal (primarily natural sugars), moderate (0 -40 grams), extreme (> 40 grams). What type of data does this represent?
a. Continuous
b. Categorical
c. Ordinal
d. Dichotomous
6. BMI is what type of data?
a. Continuous
b. Categorical
c. Ordinal
d. Dichotomous
7. The investigator asks the patients if they their mother has a history of diabetes (yes or no). What kind of data does this represent?
a. Continuous
b. Categorical
c. Ordinal
d. Dichotomous
The following are the temperatures of a group of children diagnosed with chicken pox. Use the data below to answer questions 8 - 21.
98.8 101.3 99.8 103.2 100.2 97.7 99.5 102.1 100.8 101.6
8. What is the sample mean temperature?
9. What is the sample median?
10. What is the variance?
11. What is the 25th percentile?
12. What is the 75th percentile?
13. What is the interquartile range (IQR)?
14. True or False: 97.7 is an outlier.
15. Choose from the following relative frequency histograms that correspond with the data broken into 3 groups, Group A: 97.0 - 99.9, Group B: 100.0 -101.9, Group C: 102.0 -103.9
Let's introduce a new group of temperatures, Group D: 98.5 -101.5.
16. True or False: Group A and Group D are mutually exclusive.
17. True or False: Group C and Group D are mutually exclusive.
18. What does Group B U Group D mean?
a. B and D occur = {100.0 5 temperature 101.5}
b. B and D occur = {98.5 5 temperature 5 101.9}
c. B or D occur individually or both occur simultaneously = {100.0 temperature 5 101.5}
d. B or D occur individually or both occur simultaneously = {98.5 5 temperature 101.9}
19. What does B n D mean?
a. B and D occur = {100.0 5 temperature 5 101.5}
b. B and D occur = {98.5 5 temperature 5 101.9}
c. B or D occur individually or both occur simultaneously = {100.0 5 temperature 5101.5}
d. B or D occur individually or both occur simultaneously = {98.5 5 temperature 5 101.9}
Suppose the probability of a child with chicken pox having a temperature in Group B is 25% and the probability of a child with chicken pox having temperature in Group C is 42.5%.
20. What is the probability of a child having a temperature in Group B or Group C?
21. What is the probability of a child having a temperature not in Group C?
A study relating smoking history to several measures of cardiopulmonary disability was recently reported. The data below were presented relating the number of people with different disabilities according to cigarette-smoking status.
|
Cardiopulmonary
Disability
|
Cigarette-Smoking Status
|
|
Non-Smoker
|
Ex-Smoker
|
< 15 g/day
|
≥15 g/day
|
Total
|
|
No Disability
|
565
|
628
|
595
|
456
|
|
|
Shortness of Breath
|
7
|
15
|
18
|
13
|
|
|
Angina
|
15
|
19
|
19
|
16
|
|
|
Possible Infarction
|
3
|
7
|
8
|
6
|
|
|
Total
|
|
|
|
|
2390
|
22. What is the prevalence of non-smokers in the sample?
23. What is the prevalence of no disability in the sample?
24. What is the probability of having a possible infarction AND being an ex-smoker?
25. What is the probability of angina AND a current smoker that smokes < 15 g/day?
26. What is the probability of shortness of breath given a current smoker who smokes 15 g/day (i.e. Pr(shortness of breath I 15 g/day))?
27. What is the probability of shortness of breath given a non-smoker?
28. True or False: The probability of shortness of breath and being a non-smoker are dependent events.
Exercise testing has sometimes been used to diagnose patients with coronary-artery disease. One test criterion that has been used to identify those with disease is the abnormal ejection fraction criterion; that is, an absolute rise of less than 0.05 with exercise. The validity of this noninvasive test was assessed in 196 patients versus coronary angiography, the gold standard, a procedure that can unequivocally diagnose the disease but the administration of which carries some risk for the patient.
|
|
Angiography Positive
|
Angiography Negative
|
Total
|
|
Exercise Test Positive
|
81
|
21
|
102
|
|
Exercise Test Negative
|
31
|
63
|
94
|
|
Total
|
112
|
84
|
196
|
Define screen test positive as exercise test positive and diagnostic test positive as angiography positive.
29. What is the predictive value positive?
30. What is the predictive value negative?
31. What is the sensitivity?
32. What is the specificity?
33. Suppose the prevalence of coronary artery disease is 15%. What is the new predictive value positive based on the prevalence?
34. Suppose the prevalence of coronary artery disease is 15%. What is the new predictive value negative based on the prevalence?
Use the following graph to answer questions 35 -46.
35. Which curve does not have the same mean as the other three curves?
a. Curve A
b. Curve B
c. Curve C
d. Curve D
36. Which curve has the smallest variance?
a. Curve A
b. Curve B
c. Curve C
d. Curve D
37. Which curve has the largest variance?
a. Curve A
b. Curve B
c. Curve C
d. Curve D
38. What is the mean of curve A?
39. For Curve A, what is the standardized Z-score for X = -2.5 assuming a = 1.65?
40. For Curve A, what is the Pr(X < -2.5) assuming a = 1.65?
41. What is the mean of Curve D?
42. For curve D, what is the standardized Z-score for X = 1.6 assuming a = 2.5?
43. For Curve D, what is the Pr(X > 0.64) assuming a = 2.5?
Suppose curves A, B, C, and D represent the change in temperature for new fever reducer medication. You sample 40 patients at random from Group A which has a = 1.65 and mean computed in question 38.
44. What is the standard error of the mean for Group A?
45. What is the standardized Z-score for the temperature difference of -3.2?
46. What is the standardized Z-score for no temperature difference?
A new medication has been released to treat chicken pox with an estimated probability of successful treatment of 83%. A sample of 25 patients who were recently diagnosed with chicken pox is prescribed the new medication.
47. What is the probability that exactly 22 patients will be successfully treated of the chicken pox with the new drug?
48. What is the probability that all patients will be successfully treated of the chicken pox with the new drug?
49. What is the probability that at least 22 patients will be successfully treated of the chicken pox with new drug?
50. What is the expected number of patients to be successfully treated of the chicken pox?