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A diagnostic tool with a high sensitivity and a low specificity is best used as:
A. Screening tool for the presence/absence of disease
B. Confirmatory tool for the presence/absence of disease
C. . Both for screening and confirmation of disease
D. A test to rule in a negative test result

A. Screening tool for the presence/absence of disease

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A NEW diagnostic tool for COVID-19 is discovered. Called the COVID breath test, it claims to have a sensitivity of 90% and a specificity of 95% when compared to the GOLD STANDARD of RT-PCR testing. In a population of 2750 and an COVID-19 prevalance of 3%, answer the following:
How many patients are expected to test positive for the breath test?
A. 82
B. 208
C. 5
D. 2506

A. 82

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A NEW diagnostic tool for COVID-19 is discovered. Called the COVID breath test, it claims to have a sensitivity of 90% and a specificity of 95% when compared to the GOLD STANDARD of RT-PCR testing. In a population of 2750 and an COVID-19 prevalance of 3%, answer the following:
How many patients are expected to test negative for RT-PCR?
A. 76
B. 141
C. 1845
D. 2667

D. 2667

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A NEW diagnostic tool for COVID-19 is discovered. Called the COVID breath test, it claims to have a sensitivity of 90% and a specificity of 95% when compared to the GOLD STANDARD of RT-PCR testing. In a population of 2750 and an COVID-19 prevalance of 3%, answer the following:
How many true positive test results are expected?
A. 75
B. 120
C. 226
D. 1534

A. 75

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A NEW diagnostic tool for COVID-19 is discovered. Called the COVID breath test, it claims to have a sensitivity of 90% and a specificity of 95% when compared to the GOLD STANDARD of RT-PCR testing. In a population of 2750 and an COVID-19 prevalance of 3%, answer the following:
How many true negative test results are expected?
A. 99
B. 145
C. 983
D. 2534

D. 2534

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A NEW diagnostic tool for COVID-19 is discovered. Called the COVID breath test, it claims to have a sensitivity of 90% and a specificity of 95% when compared to the GOLD STANDARD of RT-PCR testing. In a population of 2750 and an COVID-19 prevalance of 3%, answer the following:
How many false negative test results are expected?
A. 10
B. 133
C. 202
D. 1333

B. 133

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A NEW diagnostic tool for COVID-19 is discovered. Called the COVID breath test, it claims to have a sensitivity of 90% and a specificity of 95% when compared to the GOLD STANDARD of RT-PCR testing. In a population of 2750 and an COVID-19 prevalance of 3%, answer the following:
How many false positive test results are expected?
A. 8
B. 78
C. 1255
D. 2602

A. 8

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A NEW diagnostic tool for COVID-19 is discovered. Called the COVID breath test, it claims to have a sensitivity of 90% and a specificity of 95% when compared to the GOLD STANDARD of RT-PCR testing. In a population of 2750 and an COVID-19 prevalance of 3%, answer the following:
How many are expected to test negative for the breath test?
A. 68
B. 357
C. 1987
D. 2542

D. 2542

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A NEW diagnostic tool for COVID-19 is discovered. Called the COVID breath test, it claims to have a sensitivity of 90% and a specificity of 95% when compared to the GOLD STANDARD of RT-PCR testing. In a population of 2750 and an COVID-19 prevalance of 3%, answer the following:
How many are expected to test positive for the RT-PCR confirmatory test?
A. 11
B. 83
C. 567
D. 2334

B. 83

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A NEW diagnostic tool for COVID-19 is discovered. Called the COVID breath test, it claims to have a sensitivity of 90% and a specificity of 95% when compared to the GOLD STANDARD of RT-PCR testing. In a population of 2750 and an COVID-19 prevalance of 3%, answer the following:
A patient comes to you with a negative test result. What is the possibility that the test result is wrong?
A. 1%
B. 75%
C. 94%
D. 98%

A. 1%

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11.A NEW diagnostic tool for COVID-19 is discovered. Called the COVID breath test, it claims to have a sensitivity of 90% and a specificity of 95% when compared to the GOLD STANDARD of RT-PCR testing. In a population of 2750 and an COVID-19 prevalance of 3%, answer the following:
How many patients are expected to test negative for RT-PCR?
A. the value will increase
B. the value will decrease

A. the value will increase

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A lowering of the cut-off for titers for diagnosis of COVID-19 antibody will sensitivity of the test
A. the value will increase
B. the value will decrease

A. the value will increase

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Type Il or Beta Error that occurs when data lead one to conclude that something is false, when in reality, it is true. The False negative rate suggests that the test is therefore sensitive.
A. Both are True
B. Both are False
C. First is True, Second is False
D. First is False, Second is True

C. First is True, Second is False

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The lower the alpha, the lower the sample size needed.
A. True
B. False

B. False

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Five prospective cohort studies were undertaken to examine the association between bacterial vaginosis and delivery of a premature child. The results of these five hypothetical studies are illustrated in the following figure and are expressed as relative risks with 95% confidence intervals.
Which study has a p-value of >0.5 with data indicating no statistical significance?
A. B
B. A
C. C
D. E
E. D

E. D

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The direction of the relationship is enough to ascertain the strength of the association between variables.
A. True
B. False

B. False

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A new test has been developed to screen for diabetes. The following figure illustrates the distribution of values for this test among two populations. The researcher decides to use values under 20 g/dL as normal limits, and the test becomes commercially available. One of your patients has a test result of 27 ug/dL. You conclude that?
A. The patient has cancer of the diabetes
B. This is a false-negative test
C. This test is not sensitive enough to detect diabetes
D. The patient does not have diabetes
E. A confirmation test will be needed as she may or may not have diabetes

E. A confirmation test will be needed as she may or may not have diabetes

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This illustration shows
A. low precision, low accuracy
B. low precision, high accuracy
C. high precision, low accuracy
D. high precision high accuracy

C. high precision, low accuracy

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Which one is NOT a characteristic of an ideal measure dispersion?
A. it is not affected by extreme values
B. it must be easy to understand
C. it is the most unreliable measure of central tendency
D. it is least affected by sampling fluctuation

C. it is the most unreliable measure of central tendency

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A measure on how close the experimental value is to the true value is
A. accuracy
B. precision
C. both
D. neither

A. accuracy

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Five prospective cohort studies were undertaken to examine the association between bacterial vaginosis and delivery of a premature child. The results of these five hypothetical studies are illustrated in the following figure and are expressed as relative risks with 95% confidence intervals.
Which study appears to be the most precise?
A B
B. D
C. A
D. E
E. C

C. A

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The results of a study of the incidence of pulmonary tuberculosis in a village in Bacoor are given in the following table. All persons in the village are examined during two surveys made two years apart, and the number of new cases was used to determine the incidence rate. If the relative risk of the following data is calculated at 1.6% with a 95% confidence interval of 0.90-2.0. Is this risk statistically significant?
A. Cannot be determined with the data given
B. Yes, because the RR of 1.6% is within the confidence interval.
C. No, because the RR value of no difference is within the confidence interval

C. No, because the RR value of no difference is within the confidence interval

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As test specificity increases, what is the effect on PPV?
A. the value will increase
B. the value will decrease

A. the value will increase

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Statistics enables us to remove the uncertainty of the relationship between variables and approximate a 100% clarity.
A. True
B. False

B. False

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26.Which is used to summarize a big data set using less numbers? A. summarizing B. cleaning C. descriptive Statistics D. analysis

C. descriptive Statistics

27. Statistical correlation analysis is possible between qualitative variables A. True B. False

B. False

28. Categories are used as labels to distinguish one group from another A. confounders B. quantitative variables C. discrete variables D. qualitative variables

D. qualitative variables

29. Multiple variables can be correlated to show regression. A. True B. False

A. True

30. Precision pertains to all of the following EXCEPT: A. reproducibility of measurements B. agreement among numerical values C. sameness of measurements D. loseness of a measurement to an accepted value

D. loseness of a measurement to an accepted value

31. The alpha is inversely proportional to the probability of committing a Type Il error A. True B. False

A. True

32.A patient resulted negative on a certain cancer screening after biopsy patient tested positive, what can you say about the first result? A. true positive B. false positive C. true negative D. false negative

D. false negative

34. Which deals with an inspection average? A. mode B. mean

A. mode

35. The value of alpha serves as protection against: A. false negative results B. inadequate sample data C. selection bias D. type 1 error E. type I error

D. type 1 error

36. If a test of significance gives a value lower than the alpha-level, the null hypothesis is rejected. A. True B. False

A. True

37. The results of a study of the incidence of pulmonary tuberculosis in a village in Bacoor are given in the following table. All persons in the village are examined during two surveys made two years apart, and the number of new cases was used to determine the incidence rate.Interpret the result ff the calculated relative risk for this survey is at 1.6%. A. The risk of contracting pulmonary tuberculosis is higher in households with culture positive cases than households without culture positive cases B. The risk of contracting pulmonary tuberculosis is higher in households without culture positive cases than households with culture positive cases C. The risk of contracting pulmonary tuberculosis is lower in households with culture positive cases than households without culture positive cases D. Cannot be determined with the data given

A. The risk of contracting pulmonary tuberculosis is HIGHER in households with culture positive cases than households WITHOUT culture positive cases

38. Measurement that is free of random error A. accuracy B. precision C. both D. neither

D. neither

39. Which of the following deals with acute conditions and accidents or newly diagnosed cases of a particular disease? A. prevalence B. case fatality rate C. incidence rate D. general fertility rate

C. incidence rate

40. If the prevalence of a disease has been more or less constant for the past ten years (i.e., new cases have been balanced by cures or deaths of prevalent cases), what would be the effect of a treatment that prolongs the life of people suffering from the disease? A. increase prevalence B. decrease prevalence C. no effect D. cannot be predicted

A. increase prevalence

41. The smaller the probability of being wrong, the more significant is the relationship being statistically significant. A. True B. False

A. True

42. The number of persons who actually experience the event divided by the total number of persons exposed to the risk of that event is the A. relative risk B. absolute risk C. odds ratio D. None of the choices is correct

B. absolute risk

43. The extent up to which the findings of your investigation can be applied to other settings A. Internal validity B. External validity

B. External validity

44. The results of a study of the incidence of pulmonary tuberculosis in a village in Bacoor are given in the following table. All persons in the village are examined during two surveys made two years apart, and the number of new cases was used to determine the incidence rate. What is the risk difference between the exposure and non-exposure groups? A. 6.67% B. 0.75% C. 0.77% D. 3.33%

B. 0.75%

45. A new test has been developed to screen for diabetes. The following figure illustrates the distribution of values for this test among two populations. If the researcher chooses values under 25 ug/dL as normal limits for the test, which of the following statements is true? A. The test will be 100% sensitive B. There will be some false-positive tests C. All persons with cancer will have a positive test D. Some persons without cancer will test positive E. The test will be 100% specific

B. There will be some false-positive tests

46. Base on the data given: 56, 48, 35, 63, 50, 72, 67, 70, what is the Coefficient of Range? A. 35 B. 89 С. 107 D. 0.34

D. 0.34

Scenario: Initial results of a nationwide survey on the upcoming elections conducted by Trust Watch show that among 2,400 respondents, Candidate A leads over Candidate B by 23 points. To validate the results, the same study was conducted at the LRT station in Antipolo city among 300 respondents which reveals that Candidate A got 46% while candidate B has 44%, which according to the researchers is NOT statistically significant. 47. The second study does not have external validity due to A. All of the choices are correct B. The selection of respondents is biased towards those residing in Antipolo C. The 300 respondents have already been pre-tested D. the sample size of the nationwide survey is sufficient

B. The selection of respondents is biased towards those residing in Antipolo

48. A Type I error occurs when you reject a true hypothesis. A. True B. False

B. False

49. If rapidly progressive cancers are missed by a screening test, which type of bias will occur? A. Surveillance bias B. Information bias C. Selection bias D. Length bias

D. Length bias

50. The formula for a (+) likelihood ratio is A. sensitivity/1-specificity B. specificity/1 - sensitivity C. 1 - specificity/sensitivity D. 1- sensitivity.specificity

A. sensitivity/1-specificity

51. A research instrument which represents the thing that it aims to indicate is said to have validity. A. Construct B. Content C. Criterion D. Face

B. Content

52. Statistical significance is achieved when: A. alpha is greatar than or equal to p B. beta equals alpha C. p is greater than alpha D. p is greater than beta

A. alpha is greatar than or equal to p

53. The ability of a test to indicate non-disease when no disease is present can be determined with this formula A. TP / (TP + FN) B. TN / (TN + FP) C. TN / (TN + FN) D. TP / (TP + FP)

B. TN / (TN + FP)

54. A null hypothesis states that the proposed relationship is untrue A. True B. False

A. True

55. Confirmatory Test is used to "rule out" false hypotheses or differential diagnoses. It must have a high degree of sensitivity and a low FN / type II error rate. A. both are true B. Both are False C. First is True, Second is False D. First is False, Second is True

C. First is True, Second is False It must have a high degree of SPECIFICITY and a low FN / type I error rate.

56. A data collection method which is able to reflect how close measurements of the same item are to each other has which characteristic? A. Reliability B. Persistence C. Accuracy D. Validity

A. Reliability

57. An investigator is designing a randomized, double-blind, placebo-controlled clinical trial to see whether vitamin E will prevent lung cancer. Which is most likely to affect the validity (source of bias) of the study? A. Loss to follow-up B. B error C. Prevalence of smoking in the source population D. Incidence of lung cancer E. a error

A. Loss to follow-up

58. Get the Range of the given score of students in PMCH 3rd LE: 56, 48, 35, 63, 50, 72, 67, 70 A. 40 B. 52 C. 37 D. 60

C. 37

59. Ability of a test to indicate non-disease when no disease is present is A. sensitivity B. specificity C. validity D. accuracy

B. specificity

60. About 1% of boys are born with undescended testes. To determine whether prenatal exposure to tobacco smoke is a cause of undescended testes in newborns, the mothers of 100 newborns with undescended testes and those of 100 newborns whose testes had descended were questioned about smoking habits during pregnancy. The study revealed an odds ratio of 2.6 associated with exposure to smoke, with 95% confidence intervals (CI) from 1.1 to 5.3. Some reviewers are concerned that the study may overestimate the association between maternal smoking and undescended testes in the offspring because of potential A. Selection bias B. Confounding C. Loss to follow-up D. Recall bias

D. Recall bias

61. This is an introduced when a researcher fails to follow the protocol in the conduct of the study A. Random error B. Bias C. Systematic error D. Confounding

A. Random error

62. Barangay X is a community of 100,000 persons in the country. During typhoon Haiyan in 2013, there were 1,000 deaths from all causes. A study of all cases of tuberculosis found the number of deaths at 300 (200 males and 100 females). During 2012, there were only 60 deaths from tuberculosis, 50 of them males. What is the case fatality rate for tuberculosis in 2013? A. 10/1000 B. 300/100,000 C. cannot be computed from given data D. 60 per 1000 E. 66

C. cannot be computed from given data

63. The accepted value is 29.35. Which correctly describes this student's experimental data? A. accurate but not precise B. precise but not accurate C. both D. neither

C. both

64. True statement about ratios A. calculated by multiplying one interval to another B. represents the relative magnitude of two quantities C. used to compare a part to the whole D. The numerator and denominator needs to be related

B. represents the relative magnitude of two quantities

65. The mathematical formula for a straight line is y=m+b. The conceptual approach to this formula is not the same in mathematics as in statistics. In statistics: A. Only m is unknown B. the equation is irrelevant C. and y are known, and m and b are to be determined D. y is known, and x is to be determined

C. and y are known, and m and b are to be determined

66. If a biochemical test gives the same reading for a sample on repeated testing, it is inferred that the measurement is A. precise B. accurate C. specific D. sensitive

A. precise

67. Uncertainty between true value and observed value is A. error B. mistake C. blunder D. deviation

A. error

68. The degree to which the instrument measures what it purports to measure is? A. validity B. reliability C. accuracy D. precision

A. validity

69. Error that occurs when data lead one to conclude that something is true, when in reality, it is not true. A. alpha error B. beta error C. blunder D. systematic error

A. alpha error

70. ARR or OD which signifies that there is no difference in the development of the outcome of interest between the intervention and control groups A. 1.0 B. <1.0 C. >1.0

A. 1.0

71. The likelihood of its occurrence after exposure to a risk (variable) as compared with the likelihood of its occurrence in a control or reference group is referred to as A. Absolute risk B. Relative risk C. Odd ratio D. Risk difference

B. Relative risk

72. The results of a study of the incidence of pulmonary tuberculosis in a village in Bacoor are given in the following table. All persons in the village are examined during two surves made two years apart, and the number of new cases was used to determine the incidence rate. What is the absolute risk of getting pulmonary tuberculosis in the exposed group? A. 2% B. 0.15% C. .77% D. 1.96%

A. 2%

73. The results of a study of the incidence of pulmonary tuberculosis in a village in Bacoor are given in the following table. All persons in the village are examined during two surveys made two years apart, and the number of new cases was used to determine the incidence rate. What is the absolute risk of getting pulmonary tuberculosis in the non-exposed group? A. 1.25% B. 1.23% C. 2.5% D. 0.77% E. 77

A. 1.25%

74. Factors that contribute to random error include A. poor accuracy B. sampling error C. bias in measurement D. all of the above

D. all of the above

75. Five darts strike near the center of the target. Whoever threw the darts is A. accurate B. precise C. both D. neither

C. both

76. A null hypothesis is the hypothesis that states a difference between variables. A. True B. False

B. False

77. Using the same apparatus, you and your classmate had different blood pressure readings. This is an example of A. interobserver variation B. intraobserver variation C. both D. neither

A. interobserver variation

78. The extent to which a study shows a reliable cause-and-effect relationship between a treatment and an outcome denoting the ability of a study to rule out alternate causes for a result A. External validity B. Internal validity

B. Internal validity

79. The difference between a true value and an estimate, or approximation, of that value A. Confounding B. Bias C. Sampling D. Error

D. Error

80. True of confirmatory tests A. used to "rule out true hypothesis / diagnosis B. must have a high degree of specificity and a low FP / type I error rate C. must have a low degree of specificity and a low FP / type I error rate

B. must have a high degree of specificity and a low FP / type I error rate

81. A systematic distortion of the estimated intervention effect away from the "truth", caused by inadequacies in the design, conduct, or analysis of a trial A. None of the choices are correct B. Systematic error C. Both bias and systematic error are correct D. Bias

C. Both bias and systematic error are correct

82. What is the formula for sensitivity? A. TP/ТР +FN B. TN/TN +FP C. TP/ТР +FP D. TN/TN +FN

A. TP/ТР +FN

84. Regression analysis shows both magnitude and direction. A. True B. False

A. True

85. A new test has been developed to screen for diabetes. The following figure illustrates the distribution of values for this test among two populations. If the researcher chooses values under 30 ug/dL as normal limits for the test, which of the following statements is true? A. All persons with cancer will have a positive test B. There will be some false-positive tests C. Some persons without cancer will test positive D. The test will be 100% sensitive E. The test will be 100% specific

E. The test will be 100% specific

86. The results of a study of the incidence of pulmonary tuberculosis in a village in Bacoor are given in the following table. All persons in the village are examined during two surveys made two years apart, and the number of new cases was used to determine the incidence rate. Which of the following choices refers to the exposed group? A. Number of new cases in the household without culture positive cases B. Number of cases in the household with culture positive cases C. Households with culture positive cases D. Households without culture positive cases

C. Households with culture positive cases

87. You have just finished conducting a case-control study to measure the association between alcohol use and lower respiratory tract infections. The most appropriate method to control for smoking as a confounder is A. Randomization B. Stratification C. Matching

B. Stratification

88. THE first three freshman medical students taking online classes felt a lot better since they started to take anti-depressants. You conservatively make a conclusion that medical school based on online instruction is associated with depression. This is an example of: A. deductive reasoning B. hypothesis testing C. inductive reasoning D. interpolation

C. inductive reasoning

89. An error due to faulty calibration is called A. random error B. blunder C. systematic error D. standard deviation

C. systematic error

90. The results of a study of the incidence of pulmonary tuberculosis in a village in Bacoor are given in the following table. All persons in the village are examined during two surveys made two years apart, and the number of new cases was used to determine the incidence rate. What is the odds ratio in the exposed group (up to the second decimal place)? A. 1.7 B. 1.61 С. 1.60 D. Cannot be determined with the given data

B. 1.61

91. The higher disease risk in the presence of the exposure or risk factor than in the absence of the exposure is referred to as A. negative association B. no association C. relative risk D. positive association

D. positive association

92. Dr. Pascal and his team selected group of participants by random sampling and asked that group for the same information again several times over a period of time. What is the sampling method used? A. cluster sampling B. panel sampling C. purposive sampling D. snowball sampling

B. panel sampling

93. Identify which one is used when dealing with chronic conditions and disabilities or what population or group of persons are actually ill with a particular disease at a point in time? A. prevalence B. case fatality rate C. incidence D. fertility rate

A. prevalence

94. Type 1 error is the probability of finding a difference with our sample compared to population, and there really isn't one. This is usually set at 5% (or 0.05). A. both are true B. both are false C. first is true, second false D. first is false, second is true

A. both are true

95. In statistics, a result is called significant if it is unlikely to have occurred by chance. A. True B. False

B. False

96. The results of a study of the incidence of pulmonary tuberculosis in a village in Bacoor are given in the following table. All persons in the village are examined during two surveys made two years apart, and the number of new cases was used to determine the incidence rate. What is the relative risk of acquiring tuberculosis in households with a culture-positive case compared with households without tuberculosis? A. 1.6% B. 1.0% C. 0.63% D. Cannot be determined with the data given

A. 1.6%

97. The risk of an event that is specifically due to the risk factor of interest is referred to as the A. odds ratio B. attributable risk C. Number needed to treat D. relative risk

B. attributable risk

98. This is the measure of the frequency with which an event occurs in a defined population over a specified period of time A. Proportion B. Odds C. Ratio D. Rate

D. Rate

99. Where the data mislead because they are not representative of the population A. selection bias B. classification bias C. sampling bias D. validity bias E. population bias

A. selection bias

100. Five prospective cohort studies were undertaken to examine the association between bacterial vaginosis and delivery of a premature child. The results of these five hypothetical studies are illustrated in the following figure and are expressed as relative risks with 95% confidence intervals. Which study appears to have the smallest sample size? A. B B. D C. C D. A E. E

A. B

11. By mere inspection of data, what can you conclude?. * Even if clinically meaningful, the difference is not statistically significant * Even if statistically significant, the difference is probably not clinically meaningful * If clinically meaningful, the test must be statistically significant * The difference is definitely clinically meaningful

Even if statistically significant, the difference is probably not clinically meaningful

12. Before concluding that the intervention lacks statistical significance, you would want to consider:. * beta error * alpha level * critical ratio * p value * type 1 error

beta error

13. An example of a ratio used in health. * temperature * mortality rate * body mass index * case fatality rate

body mass index

15. Error that occurs when data lead one to conclude that something is true, when in reality, it is not true. * alpha error * beta error * blunder * systematic error

alpha error ## Footnote Type I / Alpha / False Positive Error: Error that occurs when data lead one to conclude that something is true, when in reality it is not true. Suggests that the test is not specific. FP Error Rate = FP / (FP + TN)

16. Which of the following about Ratio is not correct?. A. it measures quotient of two numbers without taking particular considerations to time or place B. it expressed the relative frequency of occurrence of event compared to another event C. it measures the probability of occurrence of some particular event D. ratio realizes the implications of certain data to a physicians practice

C. it measures the probability of occurrence of some particular event

18. The alpha is inversely proportional to the probability of committing a Type II error. True False

True

19. If a biochemical test gives the same reading for a sample on repeated testing, it is inferred that the measurement is_______ * precise * accurate * specific * sensitive

precise

20. If a test of significance gives a value lower than the alpha-level, the null hypothesis is rejected.. True False

True

21. An error due to faulty calibration is called. * random error * blunder * systematic error * standard deviation

systematic error

22. Which one is NOT a characteristic of an ideal measure dispersion? * it is not affected by extreme values * it must be easy to understand * it is the most unreliable measure of central tendency * it is least affected by sampling fluctuation

it is the most unreliable measure of central tendency

23. A diagnostic tool with a high sensitivity and a low specificity is best used as:. * Screening tool for the presence/absence of disease * Confirmatory tool for the presence/absence of disease Both for screening and confirmation of disease * A test to rule in a negative test result

Screening tool for the presence/absence of disease

24. An increase in disease prevalence will ____ the PPV of the test. * the value will increase * the value will decrease

the value will increase

26. Where the data mislead because they are not representative of the population. * selection bias * classification bias * sampling bias * validity bias * population bias

selection bias

28. What is the formula for sensitivity?. * TP/TP +FN * TN/TN +FP * TP/ TP +FP * TN/TN +FN

TP/TP +FN ## Footnote Sensitivity = TP/TP +FN Specificity = TN/TN +FP Positive Predictive Value = TP/ TP +FP Negative Predictive Value = TN/TN +FN

29. Barangay X is a community of 100,000 persons in the country. During typhoon Haiyan in 2013, there were 1,000 deaths from all causes. A study of all cases of tuberculosis found the number of deaths at 300 (200 males and 100 females). During 2012, there were only 60 deaths from tuberculosis, 50 of them males. What is the case fatality rate for tuberculosis in 2013?. * 10/1000 * 300/100,000 * cannot be computed from given data * 60 per 1000

cannot be computed from given data

30. True of confirmatory tests. * used to "rule out" true hypothesis / diagnosis * must have a high degree of specificity and a low FP / type I error rate * must have a low degree of specificity and a low FP / type I error rate * must have a high degree of specificity and a low FP I type Il error rate

must have a high degree of specificity and a low FP / type I error rate ## Footnote Confirmatory Tests -used to "rule in" true hypothesis / diagnosis -must have a high degree of specificity and a low FP / type I error rate

31. As test specificity increases, what is the effect on PPV?. * the value will increase * the value will decrease

the value will increase

32. Which is used to summarized a big data set using less numbers?. * summarizing * cleaning * descriptive Statistics * analysis

descriptive Statistics ## Footnote A descriptive statistic is a summary statistic that quantitatively describes or summarizes features from a collection of information, while descriptive statistics is the process of using and analysing those statistics.

33. Which of the following gives best result when deviation is taken from median? * standard deviation * mean absolute deviation * skewness * coefficient of variation

mean absolute deviation

34. The accepted value is 29.35. Which correctly describes this student’s experimental data? Trial Measurement 1 29.48 2 29.05 3 29.27. * accurate but not precise * precise but not accurate * both * neither

both

35. Using the same apparatus, you and your classmate had different blood pressure readings. This is an example of. * interobserver variation * intraobserver variation * both * neither

interobserver variation

36. Base on the data given: 56, 48, 35, 63, 50, 72, 67, 70 , what is the Co-efficient of Range?. * 35 * 89 * 107 * 34

37. This illustration shows. * low precision, low accuracy * low precision, high accuracy * high precision, low accuracy * high precision ,high accuracy

high precision, low accuracy

38. The degree to which the instrument measures what it purports to measure is?. validity reliability accuracy precision

validity

39. A patient resulted negative on a certain cancer screening after biopsy patient tested positive, what can you say about the first result?. true positive false positive true negative false negative

false negative

42. Statistics enables us to remove the uncertainty of the relationship between variables and approximates a 100% clarity. True False

False We can never be completely 100% certain that a relationship exists between two variables. There are too many sources of error to be controlled, for example, sampling error, researcher bias, problems with reliability and validity, simple mistakes, etc. Trans 24. L5.1 page 3

44. A null hypothesis is the hypothesis that states a difference between variables.. True False

False A null hypothesis usually states that there is no relationship between the two variables; a null hypothesis may also state that the relationship proposed in the research is not true.

45. Type II or Beta Error that occurs when data lead one to conclude that something is false, when in reality, it is true. The False negative rate suggests that the test is therefore sensitive. Both are True Both are False First is True, Second is False First is False, Second is True

First is True, Second is False

46. A null hypothesis states that the proposed relationship is untrue. True False

True

47. Statistical correlation analysis is possible between qualitative variables. True False

False

48. A NEW diagnostic tool for COVID-19 is discovered. Called the COVID breath test, it claims to have a sensitivity of 90% and a specificity of 95% when compared to the GOLD STANDARD of RT-PCR testing. In a population of 2750 and an COVID-19 prevalence of 3%, answer the following: How many are expected to test positive for the RT-PCR confirmatory test?. 11 83 567 2334

50. No comparison of greater or less, higher or lower, better or worse. quantitative variables qualitative variables continuous variables discrete variables

qualitative variables

52. Which deals with an inspection average?. mode mean median dispersion

mode

53. If the prevalence of a disease has been more or less constant for the past ten years (i.e., new cases have been balanced by cures or deaths of prevalent cases), what would be the effect of a treatment that prolongs the life of people suffering from the disease?. increase prevalence decrease prevalence no effect cannot be predicted

increase prevalence

54. A patient comes to you with a negative test result. What is the possibility that the test result is wrong?. 1% 75% 94% 98%

57. To determine the capability of the hospital to deliver health services, the management assessed the number of beds per population. What measure is this?. ratio rate proportion count

ratio

58. Those obtained by some other researchers for purposes not necessarily the same as those of the investigators’ and are considered as previously existing information vital Statistics statistical inference primary data secondary data

secondary data

59. A lowering of the cut-off for titers for diagnosis of COVID-19 antibody will _____ sensitivity of the test. the value will increase the value will decrease

the value will increase if we increase the sensitivity by lowering the cut-off level, we decrease the specificity Early detection, To treat the disease more aggressively, More expenses for Over-treatment

61. The lower the alpha, the lower the sample size needed. True False

False higher sample size if you want a lower alpha.

62. An alpha of 0.10 means that the probability that the hypothesis is correct is 10%. True False

True 1/5/10%

63. Age standardization needs application of a standard population. true false

true

64. The formula for a (+) likelihood ratio is. sensitivity/1-specificity specificity/1 - sensitivity 1 - specificity/sensitivity 1- sensitivity.specificity

sensitivity/1-specificity

65. Dr. Pascual and his team selected group of participants by random sampling and asked that group for the same information again several times over a period of time. What is the sampling method used?. cluster sampling panel sampling purposive sampling snowball sampling

panel sampling

69. Uncertainty between true value and observed value is. error mistake blunder deviation

error

70. Ability of a test to indicate non-disease when no disease is present is. sensitivity specificity validity accuracy

specificity

71. The value of alpha serves as protection against:. false negative results inadequate sample data selection bias type 1 error type II error

type 1 error

73. It is easier to disprove an alternative hypothesis, so the beta error is usually high compared to the alpha error. True False

True

74. Confirmatory Test is used to “rule out” false hypotheses or differential diagnoses. It must have a high degree of sensitivity and a low FN / type II error rate. both are true Both are False First is True, Second is False First is False, Second is True

Both are False

75. Type 1 error is the probability of finding a difference with our sample compared to population, and there really isn’t one. This is usually set at 5% (or 0.05) both are true both are false first is ture, second false first is false, second is true

both are true

76. Regression analysis shows both magnitude and direction.. True False

True The magnitude (VIP) and direction is a regression coefficient

77. The ability of a test to indicate non-disease when no disease is present can be determined with this formula______. TP / (TP + FN) TN / (TN + FP) TN / (TN + FN) TP / (TP + FP)

TN / (TN + FP)

78. Statistical significance is achieved when: alpha is greatar than or equal to p beta equals alpha

alpha is greatar than or equal to p

79. Multiple variables can be correlated to show regression. True False

True

80. In statistics, a result is called significant if it is unlikely to have occurred by chance. True False

False

81. A measure on how close the experimental value is to the true value is. accuracy precision both neither

accuracy

82. THE first three freshman medical students taking online classes felt a lot better since they started to take anti-depressants. You conservatively make a conclusion that medical school based on online instruction is associated with depression. This is an example of: deductive reasoning hypothesis testing inductive reasoning interpolation

inductive reasoning

84. A researcher is recording the number of individuals in a particular geographic region who have a common cold at some point during the month of February 2015. What measure of disease frequency is he doing?. count proportion rate ratio

count

85. Measurement that is free of random error. accuracy precision both neither

neither

86. Precision pertains to all of the following EXCEPT:. reproducibility of measurements agreement among numerical values sameness of measurements loseness of a measurement to an accepted value

loseness of a measurement to an accepted value

87. The direction of the relationship is enough to ascertain the strength of the association between variables. True False

False

88. The smaller the probability of being wrong, the more significant is the relationship being statistically significant True False

True

89. A Type I error occurs when you reject a true hypothesis. True False

False

90. Categories are used as labels to distinguish one group from another. confounders quantitative variables discrete variables qualitative variables

qualitative variables

91. Five darts strike near the center of the target. Whoever threw the darts is. accurate precise both neither

both

92. A complete enumeration of a population and is the best source of data on population characteristics such as size and distribution according to age, sex, marital status, and area of residence among others. demography surveillance census survey

census

94. The mathematical formula for a straight line is y=mx+b. The conceptual approach to this formula is not the same in mathematics as in statistics. In statistics:. Only m is unknown the equation is irrelevant and y are known, and m and b are to be determined y is known, and x is to be determined

and y are known, and m and b are to be determined

95. Factors that contribute to random error include. poor accuracy sampling error bias in measurement all of the above

all of the above

96. The date today is what kind of date. nominal ordinal interval ratio

interval

99. Identify which one is used when dealing with chronic conditions and disabilities or what population or group of persons are actually ill with a particular disease at a point in time? prevalence case fatality rate incidence fertility rate

prevalence

LE6 Flashcards

(166 cards)