LE6 Flashcards
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- 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%
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
- 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
- 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
- The lower the alpha, the lower the sample size needed.
A. True
B. False
B. False
- 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
- The direction of the relationship is enough to ascertain the strength of the association between variables.
A. True
B. False
B. False
- 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
- 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
- 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
- A measure on how close the experimental value is to the true value is
A. accuracy
B. precision
C. both
D. neither
A. accuracy
- 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
- 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
- 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
- Statistics enables us to remove the uncertainty of the relationship between variables and approximate a 100% clarity.
A. True
B. False
B. False
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
- Statistical correlation analysis is possible between qualitative variables
A. True
B. False
B. False
- 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
- Multiple variables can be correlated to show regression.
A. True
B. False
A. True
- 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
- 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
- Which deals with an inspection average?
A. mode
B. mean
A. mode
- 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
- If a test of significance gives a value lower than the alpha-level, the null hypothesis is rejected.
A. True
B. False
A. True
- 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
- Measurement that is free of random error
A. accuracy
B. precision
C. both
D. neither
D. neither
- 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
- 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
- The smaller the probability of being wrong, the more significant is the relationship being statistically significant.
A. True
B. False
A. True
- 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
- 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
- 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%
- 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
- 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.
- 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
- A Type I error occurs when you reject a true hypothesis.
A. True
B. False
B. False
- 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
- 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
- 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
- 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
- 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)
- A null hypothesis states that the proposed relationship is untrue
A. True
B. False
A. True
- 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.
- 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
- 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
- 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
- Ability of a test to indicate non-disease when no disease is present is
A. sensitivity
B. specificity
C. validity
D. accuracy
B. specificity
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- Uncertainty between true value and observed value is
A. error
B. mistake
C. blunder
D. deviation
A. error
- The degree to which the instrument measures what it purports to measure is?
A. validity
B. reliability
C. accuracy
D. precision
A. validity
- 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
- 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
- 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
- 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%
- 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%
- 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
- Five darts strike near the center of the target. Whoever threw the darts is
A. accurate
B. precise
C. both
D. neither
C. both
- A null hypothesis is the hypothesis that states a difference between variables.
A. True
B. False
B. False
- 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
- 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
- The difference between a true value and an estimate, or approximation, of that value
A. Confounding
B. Bias
C. Sampling
D. Error
D. Error
- 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
- 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
- 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
- Regression analysis shows both magnitude and direction.
A. True
B. False
A. True
- 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
- 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
- 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
- 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
- An error due to faulty calibration is called
A. random error
B. blunder
C. systematic error
D. standard deviation
C. systematic error
- 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
- 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
- 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
- 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
- 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
- In statistics, a result is called significant if it is unlikely to have occurred by chance.
A. True
B. False
B. False
- 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%
- 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
- 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
- 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
- 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
- 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
- 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
- An example of a ratio used in health.
* temperature
* mortality rate
* body mass index
* case fatality rate
body mass index
- 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
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)
- 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
- The alpha is inversely proportional to the probability of committing a Type II error.
True
False
True
- 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
- If a test of significance gives a value lower than the alpha-level, the null hypothesis is rejected..
True
False
True
- An error due to faulty calibration is called.
* random error
* blunder
* systematic error
* standard deviation
systematic error
- 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
- 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
- An increase in disease prevalence will ____ the PPV of the test.
* the value will increase
* the value will decrease
the value will increase
- Where the data mislead because they are not representative of the population.
* selection bias
* classification bias
* sampling bias
* validity bias
* population bias
selection bias
- What is the formula for sensitivity?.
* TP/TP +FN
* TN/TN +FP
* TP/ TP +FP
* TN/TN +FN
TP/TP +FN
Sensitivity = TP/TP +FN
Specificity = TN/TN +FP
Positive Predictive Value = TP/ TP +FP
Negative Predictive Value = TN/TN +FN
- 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
- 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
Confirmatory Tests
-used to “rule in” true hypothesis / diagnosis
-must have a high degree of specificity and a low FP / type I error rate
- As test specificity increases, what is the effect on PPV?.
* the value will increase
* the value will decrease
the value will increase
- Which is used to summarized a big data set using less numbers?.
* summarizing
* cleaning
* descriptive Statistics
* analysis
descriptive Statistics
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.
- 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
- 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
- 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
- Base on the data given: 56, 48, 35, 63, 50, 72, 67, 70 , what is the Co-efficient of Range?.
* 35
* 89
* 107
* 34
34
- This illustration shows.
* low precision, low accuracy
* low precision, high accuracy
* high precision, low accuracy
* high precision ,high accuracy
high precision, low accuracy
- The degree to which the instrument measures what it purports to measure is?.
validity
reliability
accuracy
precision
validity
- 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
- 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
- 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.
- 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
- A null hypothesis states that the proposed relationship is untrue.
True
False
True
- Statistical correlation analysis is possible between qualitative variables.
True
False
False
- 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
83
- No comparison of greater or less, higher or lower, better or worse.
quantitative variables
qualitative variables
continuous variables
discrete variables
qualitative variables
- Which deals with an inspection average?.
mode
mean
median
dispersion
mode
- 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
- A patient comes to you with a negative test result. What is the possibility that the test result is wrong?.
1%
75%
94%
98%
1%
- 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
- 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
- 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
- The lower the alpha, the lower the sample size needed.
True
False
False
higher sample size if you want a lower alpha.
- An alpha of 0.10 means that the probability that the hypothesis is correct is 10%.
True
False
True
1/5/10%
- Age standardization needs application of a standard population.
true
false
true
- The formula for a (+) likelihood ratio is.
sensitivity/1-specificity
specificity/1 - sensitivity
1 - specificity/sensitivity
1- sensitivity.specificity
sensitivity/1-specificity
- 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
- Uncertainty between true value and observed value is.
error
mistake
blunder
deviation
error
- Ability of a test to indicate non-disease when no disease is present is.
sensitivity
specificity
validity
accuracy
specificity
- 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
- It is easier to disprove an alternative hypothesis, so the beta error is usually high compared to the alpha error.
True
False
True
- 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
- 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
- Regression analysis shows both magnitude and direction..
True
False
True
The magnitude (VIP) and direction is a regression coefficient
- 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)
- Statistical significance is achieved when:
alpha is greatar than or equal to p
beta
equals alpha
alpha is greatar than or equal to p
- Multiple variables can be correlated to show regression.
True
False
True
- In statistics, a result is called significant if it is unlikely to have occurred by chance.
True
False
False
- A measure on how close the experimental value is to the true value is.
accuracy
precision
both
neither
accuracy
- 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
- 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
- Measurement that is free of random error.
accuracy
precision
both
neither
neither
- 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
- The direction of the relationship is enough to ascertain the strength of the association between variables.
True
False
False
- The smaller the probability of being wrong, the more significant is the relationship being statistically significant
True
False
True
- A Type I error occurs when you reject a true hypothesis.
True
False
False
- Categories are used as labels to distinguish one group from another.
confounders
quantitative variables
discrete variables
qualitative variables
qualitative variables
- Five darts strike near the center of the target. Whoever threw the darts is.
accurate
precise
both
neither
both
- 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
- 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
- Factors that contribute to random error include.
poor accuracy
sampling error
bias in measurement
all of the above
all of the above
- The date today is what kind of date.
nominal
ordinal
interval
ratio
interval
- 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