Pregunta 1
Pregunta
In the definition of epidemiology, "distribution" refers to EXCEPT:
Pregunta 2
Pregunta
In the definition of epidemiology, "determinants" generally includes EXCEPT:
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Agents
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Causes
-
Control measures
-
Risk factors
-
Sources
Pregunta 3
Pregunta
Epidemiology, as defined in this lesson, would NOT include which of the following activities?
Respuesta
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Describing the demographic characteristics of persons with acute aflatoxin poisoning in District A
-
Prescribing an antibiotic to treat a patient with community-acquired methicillin-resistantStaphylococcus aureus infection
-
Comparing the family history, amount of exercise, and eating habits of those with and without newly diagnosed diabetes
-
Recommending that a restaurant be closed after implicating it as the source of a hepatitis A outbreak
Pregunta 4
Pregunta
John Snow's investigation of cholera is considered a model for epidemiologic field investigations because it includes the following EXCEPT:
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Biologically plausible hypothesis
-
Comparison of a health outcome among exposed and unexposed groups
-
Multivariate statistical model
-
Spot map
-
Recommendation for public health action
Pregunta 5
Pregunta
Public health surveillance does NOT include which of the following activity:
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Diagnosing whether a case of encephalitis is actually due to West Nile virus infection
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Soliciting case reports of persons with symptoms compatible with SARs from local hospitals
-
Creating graphs of the number of dog bites by week and neighborhood
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Writing a report on trends in seat belt use to share with the state legislature
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All of the above
-
None of the above
Pregunta 6
Pregunta
The hallmark feature of an analytic epidemiologic study is:
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Use of an appropriate comparison group
-
Laboratory confirmation of the diagnosis
-
Publication in a peer-reviewed journal
-
Statistical analysis using logistic regression
Pregunta 7
Pregunta
A number of passengers on a cruise ship from Puerto Rico to the Panama Canal have recently developed a gastrointestinal illness compatible with norovirus (formerly called Norwalk-like virus). Testing for norovirus is not readily available in any nearby island, and the test takes several days even where available. Assuming you are the epidemiologist called on to board the ship and investigate this possible outbreak, your case definition should include, at a minimum:
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Clinical criteria, plus specification of time, place, and person
-
Clinical features, plus the exposure(s) you most suspect
-
Suspect cases
-
The nationally agreed standard case definition for disease reporting
Pregunta 8
Pregunta
Compare food histories between persons with Staphylococcus food poisoning and those without
Respuesta
-
Distribution
-
Determinants
-
Application
Pregunta 9
Pregunta
Compare frequency of brain cancer among anatomists with frequency in general population
Respuesta
-
Distribution
-
Determinants
-
Application
Pregunta 10
Pregunta
Mark on a map the residences of all children born with birth defects within 2 miles of a hazardous waste site
Respuesta
-
Distribution
-
Determinants
-
Application
Pregunta 11
Pregunta
Graph the number of cases of congenital syphilis by year for the country
Respuesta
-
Distribution
-
Determinants
-
Application
Pregunta 12
Pregunta
Recommend that close contacts of a child recently reported with meningococcal meningitis receive Rifampin
Respuesta
-
Distribution
-
Determinants
-
Application
Pregunta 13
Pregunta
Tabulate the frequency of clinical signs, symptoms, and laboratory findings among children with chickenpox in Cincinnati, Ohio
Respuesta
-
Distribution
-
Determinants
-
Application
Pregunta 14
Pregunta
Essay entitled “On Airs, Waters, and Places,” suggested that environmental and host factors such as behaviors
Respuesta
-
Hippocrates
-
John Graunt
-
John Snow
Pregunta 15
Pregunta
first to quantify patterns of birth, death, and disease occurrence, noting disparities between males and females, high infant mortality, urban/rural differences, and seasonal variations
Respuesta
-
John Graunt
-
John Snow
-
William Farr
Pregunta 16
Pregunta
Father of modern vital statistics and surveillance
Respuesta
-
William Farr
-
John Snow
-
John Graunt
Pregunta 17
Pregunta
Father of field epidemiology
Respuesta
-
John Graunt
-
John Snow
-
William Farr
Pregunta 18
Pregunta
Study linking lung cancer to smoking
Respuesta
-
Doll and Hill
-
John Snow
-
Kannel
Pregunta 19
Pregunta
Reviewing reports of test results for Chlamydia trachomatis from public health clinics
Pregunta 20
Pregunta
Meeting with directors of family planning clinics and college health clinics to discuss Chlamydia testing and reporting
Pregunta 21
Pregunta
Developing guidelines/criteria about which patients coming to the clinic should be screened (tested) for Chlamydia infection
Pregunta 22
Pregunta
Interviewing persons infected with Chlamydia to identify their sex partners
Pregunta 23
Pregunta
Conducting an analysis of patient flow at the public health clinic to determine waiting times for clinic patients
Pregunta 24
Pregunta
Comparing persons with symptomatic versus asymptomatic Chlamydia infection to identify predictors
Pregunta 25
Pregunta
Comparing numbers and rates of illness in a community, rates are preferred for
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Conducting surveillance for communicable diseases
-
Deciding how many doses of immune globulin are needed
-
Estimating subgroups at highest risk
-
Telling physicians which strain of influenza is most prevalent
Pregunta 26
Pregunta
For the cruise ship scenario described in Question 7, how would you display the time course of the outbreak?
Respuesta
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Endemic curve
-
Epidemic curve
-
Seasonal trend
-
Secular trend
Pregunta 27
Pregunta
For the cruise ship scenario described in Question 7, if you suspected that the norovirus may have been transmitted by ice made or served aboard ship, how might you NOT display "place"?
Respuesta
-
Spot map by assigned dinner seating location
-
Spot map by cabin
-
Shaded map of United States by state of residence
-
Shaded map by whether passenger consumed ship's ice or no
Pregunta 28
Pregunta
Which variables might you include in characterizing the outbreak described in Question 7 by person?
Pregunta 29
Pregunta
When analyzing surveillance data by age, which of the following age groups is preferred?
Respuesta
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1-year age groups
-
5-year age groups
-
10-year age groups
-
Depends on the disease
Pregunta 30
Pregunta
A study in which children are randomly assigned to receive either a newly formulated vaccine or the currently available vaccine, and are followed to monitor for side effects and effectiveness of each vaccine, is an example of which type of study?
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Cohort
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Case-control
-
Clinical trial
-
Cross Sectional
Pregunta 31
Pregunta
The Iowa Women's Health Study, in which researchers enrolled 41,837 women in 1986 and collected exposure and lifestyle information to assess the relationship between these factors and subsequent occurrence of cancer, is an example of which type(s) of study?
Respuesta
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Cohort
-
Case-control
-
Clinical trial
-
Cross Sectional
Pregunta 32
Pregunta
British investigators conducted a study to compare measles-mumps-rubella (MMR) vaccine history among 1,294 children with pervasive development disorder (e.g., autism and Asperger's syndrome) and 4,469 children without such disorders. (They found no association.) This is an example of which type(s) of study?
Respuesta
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Cohort
-
Case-control
-
Clinical trial
-
Cross Sectional
Pregunta 33
Pregunta
A cohort study differs from a case-control study in that:
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Subjects are enrolled or categorized on the basis of their exposure status in a cohort study but not in a case-control study
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Subjects are asked about their exposure status in a cohort study but not in a case-control study
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Cohort studies require many years to conduct, but case-control studies do not
-
Cohort studies are conducted to investigate chronic diseases, case-control studies are used for infectious diseases
Pregunta 34
Pregunta
A key feature of a cross-sectional study EXCEPT:
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It usually provides information on prevalence rather than incidence
-
It is limited to health exposures and behaviors rather than health outcomes
-
It is more useful for descriptive epidemiology than it is for analytic epidemiology
-
It is synonymous with survey
Pregunta 35
Pregunta
The epidemiologic triad of disease causation refers to
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Agent, host, environment
-
Time, place, person
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Source, mode of transmission, susceptible host
-
John Snow, Robert Koch, Kenneth Rothman
Pregunta 36
Pregunta
For each of the following, identify the appropriate letter from the time line in Figure 1.27 representing the natural history of disease.
Respuesta
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Onset of symptoms
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Usual time of diagnosis
-
Exposure
-
Latency Period
Pregunta 37
Pregunta
For each of the following, identify the appropriate letter from the time line in Figure 1.27 representing the natural history of disease.
Respuesta
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Exposure
-
Onset of symptoms
-
Pathologic Changes
-
Usual Time of Diagnosis
Pregunta 38
Pregunta
For each of the following, identify the appropriate letter from the time line in Figure 1.27 representing the natural history of disease.
Respuesta
-
Exposure
-
Onset of symptoms
-
Usual Time of Diagnosis
-
Pathologic Changes
Pregunta 39
Pregunta
For each of the following, identify the appropriate letter from the time line in Figure 1.27 representing the natural history of disease.
Respuesta
-
Exposure
-
Onset of symptoms
-
Usual Time of Diagnosis
-
Pathologic Changes
Pregunta 40
Pregunta
A reservoir of an infectious agent can be:
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An asymptomatic human
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A symptomatic human
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An animal
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The environment
-
All of the above
Pregunta 41
Pregunta
Indirect transmission includes which of the following EXCEPT?
Pregunta 42
Pregunta
Disease control measures are generally directed at which of the followingEXXCEPT ?
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Eliminating the reservoir
-
Eliminating the vector
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Eliminating the host
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Interrupting mode of transmission
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Reducing host susceptibility
Pregunta 43
Pregunta
Disease 1: usually 40–50 cases per week; last week, 48 cases
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Endemic
-
Outbreak
-
Pandemic
-
Sporadic
Pregunta 44
Pregunta
Disease 2: fewer than 10 cases per year; last week, 1 case
Respuesta
-
Endemic
-
Outbreak
-
Pandemic
-
Sporadic
Pregunta 45
Pregunta
Disease 3: usually no more than 2–4 cases per week; last week, 13 cases
Respuesta
-
Endemic
-
Outbreak
-
Pandemic
-
Sporadic
Pregunta 46
Pregunta
A propagated epidemic is usually the result of what type of exposure?
Pregunta 47
Pregunta
Which of the following are frequency measures?
Respuesta
-
Birth rate
-
Incidence
-
Mortality rate
-
Prevalence
Pregunta 48
Pregunta
In a state that did not require varicella (chickenpox) vaccination, a boarding school experienced a prolonged outbreak of varicella among its students that began in September and continued through December. To calculate the probability or risk of illness among the students, which denominator would you use?
Respuesta
-
Number of susceptible students at the ending of the period (i.e., June)
-
Number of susceptible students at the midpoint of the period (late October/early November)
-
Number of susceptible students at the beginning of the period (i.e., September)
-
Average number of susceptible students during outbreak
Pregunta 49
Pregunta
All proportions are ratios, but not all ratios are proportions.
Pregunta 50
Pregunta
Many of the students at the boarding school, including 6 just coming down with varicella, went home during the Thanksgiving break. About 2 weeks later, 4 siblings of these 6 students (out of a total of 10 siblings) developed varicella. The secondary attack rate among siblings was, therefore,:
Respuesta
-
4 ⁄ 6
-
4 ⁄ 10
-
4 ⁄ 16
-
6 ⁄ 10
Pregunta 51
Pregunta
Investigators enrolled 100 diabetics without eye disease in a cohort (follow-up) study. The results of the first 3 years were as follows:
Year 1: 0 cases of eye disease detected out of 92; 8 lost to follow-up
Year 2: 2 new cases of eye disease detected out of 80; 2 had died; 10 lost to follow-up
Year 3: 3 new cases of eye disease detected out of 63; 2 more had died; 13 more lost to follow-up
The person-time incidence rate is calculated as:
Respuesta
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5 ⁄ 100
-
5 ⁄ 63
-
5 ⁄ 235
-
5 ⁄ 250
Pregunta 52
Pregunta
The units for the quantity you calculated in Question 8 could be expressed as:
Pregunta 53
Pregunta 54
Pregunta
Generally preferred for chronic diseases without clear date of onset
Pregunta 55
Pregunta
Used in calculation of risk ratio
Pregunta 56
Pregunta
Affected by duration of illness
Pregunta 57
Pregunta
Use the following information for Questions 57–61.
Within 10 days after attending a June wedding, an outbreak of cyclosporiasis occurred among attendees. Of the 83 guests and wedding party members, 79 were interviewed; 54 of the 79 met the case definition. The following two-by-two table shows consumption of wedding cake (that had raspberry filling) and illness status.
Ate wedding cake? Ill Well Total
Yes 50 3 53
No 4 22 26
Total 54 25 79
The fraction 54 ⁄ 79 is a/an:
Pregunta 58
Pregunta
The fraction 50 ⁄ 54 is a/an:
Pregunta 59
Pregunta
The fraction 50 ⁄ 53 is a/an:
Pregunta 60
Pregunta
The best measure of association to use for these data is a/an:
Pregunta 61
Pregunta
The best estimate of the association between wedding cake and illness is:
Respuesta
-
6.1
-
7.7
-
68.4
-
83.7
-
91.7
-
94.3
Pregunta 62
Pregunta
The attributable proportion for wedding cake is:
Respuesta
-
6.1%
-
7.7%
-
68.4%
-
83.7%
-
91.7%
-
94.3%
Pregunta 63
Pregunta
Use the following diagram for Questions 63 and 64. Assume that the horizontal lines in the diagram represent duration of illness in 8 different people, out of a community of 700.
What is the prevalence of disease during July?
Respuesta
-
3 ⁄ 700
-
4 ⁄ 700
-
5 ⁄ 700
-
8 ⁄ 700
Pregunta 64
Pregunta
What is the incidence of disease during July?
Respuesta
-
3 ⁄ 700
-
4 ⁄ 700
-
5 ⁄ 700
-
8 ⁄ 700
Pregunta 65
Pregunta
Which of the following mortality rates use the estimated total mid-year population as its denominator?
Respuesta
-
Age-specific mortality rate
-
Sex-specific mortality rate
-
Crude mortality rate
-
Cause-specific mortality rate
Pregunta 66
Pregunta
Vaccine efficacy measures are:
Respuesta
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The proportion of vaccinees who do not get the disease
-
1 − the attack rate among vaccinees
-
The proportionate reduction in disease among vaccinees
-
1 − disease attributable to the vaccine
Pregunta 67
Pregunta
To study the causes of an outbreak of aflatoxin poisoning in Africa, investigators conducted a case-control study with 40 case-patients and 80 controls. Among the 40 poisoning victims, 32 reported storing their maize inside rather than outside. Among the 80 controls, 20 stored their maize inside. The resulting odds ratio for the association between inside storage of maize and illness is:
Pregunta 68
Pregunta
The crude mortality rate in Community A was higher than the crude mortality rate in Community B, but the age-adjusted mortality rate was higher in Community B than in Community A. This indicates that:
Respuesta
-
Investigators made a calculation error
-
No inferences can be made about the comparative age of the populations from these data
-
The population of Community A is, on average, older than that of Community B
-
The population of Community B is, on average, older than that of Community A
Pregunta 69
Pregunta
public health surveillance includes which activities EXCEPT?
Respuesta
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Data collection.
-
Data analysis.
-
Data interpretation.
-
Data dissemination.
-
Disease control.
Pregunta 70
Pregunta
Current public health surveillance targets which of the following?
Pregunta 71
Pregunta
Public health surveillance can be described primarily as which of the following?
Respuesta
-
A method to monitor occurrences of public health problems.
-
A program to control disease outbreaks.
-
A system for collecting health-related information.
-
A system for monitoring persons who have been exposed to a communicable disease.
Pregunta 72
Pregunta
Public health surveillance is only conducted by public health agencies.
Pregunta 73
Pregunta
Common uses and applications of public health surveillance include which of the following?
Respuesta
-
Detecting individual persons with malaria so that they can receive prompt and appropriate treatment.
-
Helping public health officials decide how to allocate their disease control resources.
-
Identifying changes over time in the proportion of children with elevated blood lead levels in a community.
-
Documenting changes in the incidence of varicella (chickenpox), if any, after a law requiring varicella vaccination took effect.
-
All of the above
Pregunta 74
Pregunta
Data collected through which of the following methods is NOT commonly used for surveillance?
Pregunta 75
Pregunta
Health-care providers might be important sources of surveillance data used by public health officials, and they should receive feedback to close the surveillance loop as a courtesy; however, the results almost never have any relevance to patient care provided by those health-care providers.
Pregunta 76
Pregunta
Vital statistics are important sources of data on which of the following?
Pregunta 77
Pregunta
Vital statistics provide an archive of certain health data. These data do not become surveillance data until they are analyzed, interpreted, and disseminated with the intent of influencing public health decision-making or action.
Pregunta 78
Pregunta
Key sources of morbidity data include which of the following EXCEPT?
Pregunta 79
Pregunta
Notifiable disease surveillance usually focuses on morbidity from the diseases on the list and does not cover mortality from those diseases.
Pregunta 80
Pregunta
The list of diseases that a physician must report to the local health department is typically compiled by the…
Pregunta 81
Pregunta
A physician working in an emergency room in Town A, USA, has just examined a tourist from Southeast Asia with watery diarrhea. The physician suspects the man might have cholera. The physician should notify the …
Respuesta
-
Local (town or county) health agency.
-
State health department.
-
Centers for Disease Control and Prevention (CDC).
-
U.S. Department of State.
-
Washington, D.C., embassy of country of origin (ask for health attaché).
Pregunta 82
Pregunta
[blank_start]Notifiable disease surveillance[blank_end] State-based, with subsequent reporting to CDC.
Pregunta 83
Pregunta
[blank_start]Notifiable disease surveillance[blank_end]Focused on identifying individual cases.
Pregunta 84
Pregunta
[blank_start]Both[blank_end]
Can monitor trends over time.
Pregunta 85
Pregunta
Based on statistically valid sample.
Pregunta 86
Pregunta
Complete, unbiased reporting
Pregunta 87
Pregunta
Evaluating and improving surveillance should address which of the following EXCEPT?
Respuesta
-
Purpose and objectives of surveillance.
-
Resources needed to conduct surveillance.
-
Effectiveness of measures for controlling the disease under surveillance.
-
Presence of characteristics of well-conducted surveillance.
Pregunta 88
Pregunta
Criteria for prioritizing health problems for surveillance include which of the following EXCEPT?
Respuesta
-
Incidence of the problem.
-
Public concern about the problem.
-
Number of previous studies of the problem.
-
Social and economic impact of the problem.
Pregunta 89
Pregunta
Watches for individual cases of disease of public health importance.
Respuesta
-
Surveillance based on a specific case definition for a disease (e.g., listeriosis).
-
Syndromic surveillance based on symptoms, signs, or other characteristics of a disease, rather than specific clinical or laboratory diagnostic criteria.
-
Both.
-
Neither
Pregunta 90
Pregunta
Watches for diseases that might be caused by acts of biologic or chemical terrorism.
Respuesta
-
Surveillance based on a specific case definition for a disease (e.g., listeriosis).
-
Syndromic surveillance based on symptoms, signs, or other characteristics of a disease, rather than specific clinical or laboratory diagnostic criteria.
-
Both.
-
Neither
Pregunta 91
Pregunta
Can watch for disease before a patient seeks care from a health-care provider.
Respuesta
-
Surveillance based on a specific case definition for a disease (e.g., listeriosis).
-
Syndromic surveillance based on symptoms, signs, or other characteristics of a disease, rather than specific clinical or laboratory diagnostic criteria.
-
Both.
-
Neither
Pregunta 92
Pregunta
Requires little effort on the part of the health department.
Respuesta
-
Surveillance based on a specific case definition for a disease (e.g., listeriosis).
-
Syndromic surveillance based on symptoms, signs, or other characteristics of a disease, rather than specific clinical or laboratory diagnostic criteria.
-
Both
-
Neither
Pregunta 93
Pregunta
Routine analysis of notifiable disease surveillance data at the state health department might NOT include looking at the number of cases of a disease reported this week …
Respuesta
-
and during the previous 2–4 weeks.
-
and the number reported during the comparable weeks of the previous 2–5 years.
-
simultaneously by age, race, and sex of the patient.
-
by county.
-
by county, divided by each county's population (i.e., county rates).
Pregunta 94
Pregunta
One week, a state health department received substantially more case reports of a disease in one county than had been reported during the previous 2 weeks. No increase was reported in neighboring counties. Possible explanations for this increase include which of the following?
Pregunta 95
Pregunta
The primary reason for preparing and distributing periodic surveillance summaries is which of the following?
Respuesta
-
Document recent epidemiologic investigations.
-
Provide timely information on disease patterns and trends to those who need to know it.
-
Provide reprints ofMMWR articles, reports, and recommendations.
-
Acknowledge the contributions of those who submitted case reports.
Pregunta 96
Pregunta
Surveillance detected 23 of 30 actual cases of a disease.
Pregunta 97
Pregunta
Of 16 statistically significant aberrations (deviations from baseline) detected by syndromic surveillance, only one represented an actual outbreak of disease.
Pregunta 98
Pregunta
Underreporting is not a problem for detecting outbreaks of notifiable diseases because the proportion of cases reported tends to remain relatively stable over time.
Pregunta 99
Pregunta
Initiating surveillance for a public health problem or adding a disease to the notifiable disease list is justified for which of the following reason?
Respuesta
-
If it is a communicable disease with a high case-fatality rate.
-
If the problem is new and systematically collected data are needed to characterize the disease and its impact on the public.
-
If a program at CDC has recommended its addition to better understand national trends and patterns.
-
all of the above
Pregunta 100
Pregunta
The case definition used for surveillance of a health problem should be the same as the case definition used for clinical (treatment) purposes.
Pregunta 101
Pregunta
A state health department decides to strengthen its notifiable disease reporting. The one best action to take is to …
Respuesta
-
allow reporting through use of the Internet.
-
require more disease-specific forms from local health departments.
-
ensure that all persons with a responsibility to report understand the requirements and reasons for reporting and how reports will be used.
-
reduce the number of diseases on the list.
Pregunta 102
Pregunta
Which of the following best describes the similarities and differences in the three distributions shown in Figure 2.11?
Respuesta
-
Same mean, median, mode; different standard deviation
-
Same mean, median, mode; same standard deviation
-
Different mean, median, mode; different standard deviation
-
Different mean, median, mode; same standard deviation
Pregunta 103
Pregunta
Which of the following terms accurately describe the distribution shown in Figure 2.12?
Respuesta
-
Negatively skewed
-
Positively skewed
-
Symmetrical
Pregunta 104
Pregunta
What is the likely relationship between mean, median, and mode of the distribution shown in Figure 2.12?
Pregunta 105
Pregunta
The mode is the value that:
Respuesta
-
Is midway between the lowest and highest value
-
Occurs most often
-
Has half the observations below it and half above it
-
Is statistically closest to all of the values in the distribution
Pregunta 106
Pregunta
The median is the value that:
Respuesta
-
Is midway between the lowest and highest value
-
Occurs most often
-
Has half the observations below it and half above it
-
Is statistically closest to all of the values in the distribution
Pregunta 107
Pregunta
Is statistically closest to all of the values in the distribution
Respuesta
-
Is midway between the lowest and highest value
-
Occurs most often
-
Has half the observations below it and half above it
-
Is statistically closest to all of the values in the distribution
Pregunta 108
Pregunta
The geometric mean is the value that:
Respuesta
-
Is midway between the lowest and highest value on a log scale
-
Occurs most often on a log scale
-
Has half the observations below it and half above it on a log scale
-
Is statistically closest to all of the values in the distribution on a log scale
Pregunta 109
Pregunta
In epidemiology, the measure of central location generally preferred for summarizing skewed data such as incubation periods is the:
Respuesta
-
Mean
-
Median
-
Midrange
-
Mode
Pregunta 110
Pregunta
The measure of central location generally preferred for additional statistical analysis is the:
Respuesta
-
Mean
-
Median
-
Midrange
-
Mode
Pregunta 111
Pregunta
Which of the following is NOT considered measures of spread?
Respuesta
-
Interquartile range
-
Percentile
-
Range
-
Standard deviation
Pregunta 112
Pregunta
The measure of spread most affected by one extreme value is the:
Respuesta
-
Interquartile range
-
Range
-
Standard deviation
-
Mean
Pregunta 113
Pregunta
The interquartile range covers what proportion of a distribution?
Pregunta 114
Pregunta
The measure of central location most commonly used with the interquartile range is the:
Respuesta
-
Arithmetic mean
-
Geometric mean
-
Median
-
Midrange
-
Mode
Pregunta 115
Pregunta
The measure of central location most commonly used with the standard deviation is the:
Respuesta
-
Arithmetic mean
-
Median
-
Midrange
-
Mode
Pregunta 116
Pregunta
The algebraic relationship between the variance and standard deviation is that:
Respuesta
-
The standard deviation is the square root of the variance
-
The variance is the square root of the standard deviation
-
The standard deviation is the variance divided by the square root of n
-
The variance is the standard deviation divided by the square root of n
Pregunta 117
Pregunta
Before calculating a standard deviation, one should ensure that:
Respuesta
-
The data are somewhat normally distributed
-
The total number of observations is at least 50
-
The variable is an interval-scale or ratio-scale variable
-
All of the above
Pregunta 118
Pregunta
Simply by scanning the values in each distribution below, identify the distribution with the largest standard deviation.
Respuesta
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1, 10, 15, 18, 20, 20, 22, 25, 30, 39
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1, 3, 8, 10, 20, 20, 30, 32, 37, 39
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1, 15, 17, 19, 20, 20, 21, 23, 25, 39
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41, 42, 43, 44, 45, 45, 46, 47, 48, 49
Pregunta 119
Pregunta
Given the area under a normal curve, which two of the following ranges are the same? (Circle the TWO that are the same.)
Respuesta
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From the 2.5th percentile to the 97.5th percentile
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From the 5th percentile to the 95th percentile
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From the 25th percentile to the 75th percentile
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From 1 standard deviation below the mean to 1 standard deviation above the mean
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None of the above
Pregunta 120
Pregunta
The primary use of the standard error of the mean is in calculating the:
Respuesta
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confidence interval
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error rate
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standard deviation
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variance
Pregunta 121
Pregunta
Tables and graphs are NOT important tools for which tasks of an epidemiologist?
Pregunta 122
Pregunta
A table in a report or manuscript should include EXCEPT:
Respuesta
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Title
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Row and column labels
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Footnotes that explain abbreviations, symbols, exclusions
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Source of the data
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Explanation of the key findings
Pregunta 123
Pregunta
The following table is unacceptable because the percentages add up to 99.9% rather than 100.0%
Age group No. Percent
< 1 year 10 19.6
1–4 9 17.6
5–9 9 17.6
10–14 17 33.3
≥15 6 11.8
Total 53
Pregunta 124
Pregunta
In the following table, the total number of persons with the disease is:
Cases Controls Total
Exposed 22 12 34
Unexposed 3 13 16
Total 25 25 50
Pregunta 125
Pregunta
A table shell is the:
Respuesta
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Box around the outside of a table
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Lines ("skeleton") of a table without the labels or title
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Table with data but without the title, labels or data
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Table with labels and title but without the data
Pregunta 126
Pregunta
The best time to create table shells is:
Respuesta
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Just before planning a study
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As part of planning the study
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Just after collecting the data
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Just before analyzing the data
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As part of analyzing the data
Pregunta 127
Pregunta
Recommended methods for creating categories for continuous variables include:
Respuesta
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Basing the categories on the mean and standard deviation
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Dividing the data into categories with similar numbers of observations in each
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Dividing the range into equal class intervals
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Using categories that have been used in national surveillance summary reports
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Using the same categories as your population data are grouped
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All of the above
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None of the above
Pregunta 128
Pregunta
In frequency distributions, observations with missing values should be excluded.
Pregunta 129
Pregunta
The following are reasonable categories for a disease that mostly affects people over age 65 years:
Age Group
< 65 years
65–70
70–75
75–80
80–85
85
Pregunta 130
Pregunta
In general, before you create a graph to display data, you should put the data into a table.
Pregunta 131
Pregunta
On an arithmetic-scale line graph, the x-axis and y-axis each should:
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Begin at zero on each axis
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Have labels for the tick marks and each axis
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Use the same tick mark spacing on the two axes
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All of the above
Pregunta 132
Pregunta
[blank_start]Semilogarithmic-scale line graph[blank_end]A wide range of values can be plotted and seen clearly, regardless of magnitude
Pregunta 133
Pregunta
[blank_start]Arithmetic-scale line graph[blank_end]A constant rate of change would be represented by a curved line
Pregunta 134
Pregunta
[blank_start]Semilogarithmic-scale line graph[blank_end]The y-axis tick labels could be 0.1, 1, 10, and 100
Pregunta 135
Pregunta
[blank_start]Both[blank_end]
Can plot numbers or rates
Pregunta 136
Pregunta
[blank_start]Bar chart[blank_end]Used for categorical variables on the x-axis
Respuesta
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Bar chart
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Histogram
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Both
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Neither
Pregunta 137
Pregunta
[blank_start]Both[blank_end]
Columns can be subdivided with color or shading to show subgroups
Respuesta
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Both
-
Bar Chart
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Histogram
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Neither
Pregunta 138
Pregunta
[blank_start]Histogram[blank_end]Displays continuous data
Respuesta
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Histogram
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Bar chart
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Both
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Neither
Pregunta 139
Pregunta
[blank_start]Histogram[blank_end] Epidemic curve
Respuesta
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Histogram
-
Bar Chart
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Both
-
Neither
Pregunta 140
Pregunta
Which of the following shapes of a population pyramid is most consistent with a young population?
Respuesta
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Tall, narrow rectangle
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Short, wide rectangle
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Triangle base down
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Triangle base up
Pregunta 141
Pregunta
A frequency polygon differs from a line graph because a frequency polygon:
Respuesta
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Displays a frequency distribution; a line graph plots data points
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Can show percentages on the y-axis; a line graph cannot
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Cannot be used to plot data over time
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All of the above
Pregunta 142
Pregunta
Y-axis shows percentages from 0% to 100%
Pregunta 143
Pregunta
Plotted curve usually begins in the upper left corner
Pregunta 144
Pregunta
Plotted curve usually begins in the lower left corner
Pregunta 145
Pregunta
Horizontal line drawn from 50% tick mark to plotted curve intersects at median
Pregunta 146
Pregunta
A scatter diagram is the graph of choice for plotting:
Respuesta
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Anabolic steroid levels measured in both blood and urine among a group of athletes
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Mean cholesterol levels over time in a population
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Infant mortality rates by mean annual income among different countries
-
Systolic blood pressure by eye color (brown, blue, green, other) measured in each person
Pregunta 147
Pregunta
Which of the following requires more than one variable?
Respuesta
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Frequency distribution
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One-variable table
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Pie chart
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Scatter diagram
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Simple bar chart
Pregunta 148
Pregunta
Compared with a scatter diagram, a dot plot:
Respuesta
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Is another name for the same type of graph
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Differ because a scatter diagram plots two continuous variables; a dot plot plots one continuous and one categorical variable
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Differ because a scatter diagram plots one continuous and one categorical variable; a dot plot plots two continuous variables
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Plots location of cases on a map
Pregunta 149
Pregunta
A spot map must reflect numbers; an area map must reflect rates.
Pregunta 150
Pregunta
To display different rates on an area map using different colors, select different colors that have the same intensity, so as not to bias the audience.
Pregunta 151
Pregunta
In an oral presentation, three-dimensional pie charts and three-dimensional columns in bar charts are desirable because they add visual interest to a slide.
Pregunta 152
Pregunta
A 100% component bar chart shows the same data as a stacked bar chart. The key difference is in the units on the x-axis.
Pregunta 153
Pregunta
When creating a bar chart, the decision to use vertical or horizontal bars is usually based on:
Respuesta
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The magnitude of the data being graphed and hence the scale of the axis
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Whether the data being graphed represent numbers or percentages
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Whether the creator is an epidemiologist (who almost always use vertical bars)
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Which looks better, such as whether the label fits below the bar
Pregunta 154
Pregunta
[blank_start]Grouped bar chart[blank_end] Number of cases of dog bites by age group (adult or child) and sex of the victim
Respuesta
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Grouped bar chart
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Histogram
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Line graph
-
Pie chart
Pregunta 155
Pregunta
[blank_start]Pie chart[blank_end]Number of cases of dog bites by breed of the dog
Respuesta
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Pie chart
-
Grouped bar chart
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Histogram
-
Line graph
Pregunta 156
Pregunta
[blank_start]Line graph[blank_end]Number of cases of dog bites per 100,000 population over time
Respuesta
-
Line graph
-
Grouped bar chart
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Histogram
-
Pie Chart
Pregunta 157
Pregunta
Number of cases of dog bites over time
Respuesta
-
Grouped bar chart
-
Histogram
-
Line graph
-
Pie chart
Pregunta 158
Pregunta
Which are the most common ways that a local health department uncovers outbreaks?
Respuesta
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Performing descriptive analysis of surveillance data each week
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Performing time series analysis to detect deviations from expected values based on the previous few weeks and comparable periods during the previous few years
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Receiving calls from affected residents
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Receiving calls from healthcare providers
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Reviewing all case reports received each week to detect common features
Pregunta 159
Pregunta
Factors that influence a health department's decision whether or not to conduct a field investigation in response to one or more cases of disease include
Pregunta 160
Pregunta
If a particular outbreak presents an unusual opportunity to learn more about the disease and its epidemiology by conducting a study, but early disease control measures would interfere with the study, one should conduct the study quickly, then implement control measures immediately afterwards.
Pregunta 161
Pregunta
Outbreak with known causative agent, source, and mode of transmission
Pregunta 162
Pregunta
Outbreak with known causative agent, but unknown source and mode of transmission
Respuesta
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Disease control and prevention efforts take priority over investigation efforts
Investigation efforts take priority over disease control and prevention efforts
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If the agent is known but the source and mode of transmission are not known (example: Salmonella eventually traced to marijuana), then the health department does not know how to target its intervention. Investigation to learn the source and/or mode is necessary.
Pregunta 163
Pregunta
Outbreak with unknown causative agent, source, and mode of transmission
Pregunta 164
Pregunta
Use the following steps of an outbreak investigation for Question 5:
1. Analyze data by time, place, and person
2. Conduct a case-control study
3. Generate hypotheses
4. Conduct active surveillance for additional cases
5. Verify the diagnosis
6. Confirm that the number of cases exceeds the expected number
7. Talk with laboratorians about specimen collection
For an investigation of an outbreak, what is the logical conceptual order of the steps listed above?
Respuesta
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1-2-3-4-5-6-7
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5-6-4-1-2-3-7
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6-5-3-1-2-7-4
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6-5-7-4-1-3-2
Pregunta 165
Pregunta
To avoid skipping a critical step, investigators should conduct the steps of an outbreak investigation in the precise order you answered in Question 164.
Pregunta 166
Pregunta
200 cases of Marburg virus infection in several districts in Angola over several months (usually none)
Respuesta
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Cluster
-
Epidemic
-
Outbreak
Pregunta 167
Pregunta
40 cases ofSalmonella Enteritidis in 1 week traced to a single meal served at a cafeteria (usually none)
Respuesta
-
Cluster
-
Epidemic
-
Outbreak
Pregunta 168
Pregunta
10 cases of cancer diagnosed over 2 years among residents of a single neighborhood (previous data not available)
Respuesta
-
Cluster
-
Epidemic
-
Outbreak
Pregunta 169
Pregunta
Why should an investigator who has no clinical background nonetheless talk to a patient or two as an early step in the outbreak investigation?
Respuesta
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To advise the patient about common risk factors and the usual course of the illness, after reviewing such information in appropriate reference material
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To develop hypotheses about the cause of the outbreak
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To learn more about the clinical manifestations of the disease
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To verify the clinical findings as part of verifying the diagnosis
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To verify the laboratory findings as part of verifying the diagnosis
Pregunta 170
Pregunta
A case definition during an outbreak investigation should NOT specify:
Respuesta
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Clinical features
-
Time
-
Place
-
Person
-
Hypothesized exposure
Pregunta 171
Pregunta
Ideally, a case definition is 100% accurate in identifying who does and does not have the disease in question, but in reality few case definitions achieve this ideal.
Pregunta 172
Pregunta
Once a case definition for an outbreak investigation has been established, it should not be changed.
Pregunta 173
Pregunta
Common methods of identifying additional cases (expanding surveillance) as part of an outbreak investigation include:
Respuesta
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Advising the public through newspapers, TV, radio, and the health department's website to contact the local health department
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Asking case-patients who they were with at the time of exposure (if known)
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Sending a fax to healthcare providers
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Telephoning the infection control practitioners at local hospitals
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All of the above
-
None of the above
Pregunta 174
Pregunta
A case report form devised for an outbreak investigation usually includes which of the following types of information?
Pregunta 175
Pregunta
Descriptive epidemiology is essential for "characterizing the outbreak" by time, place, and person, but has little bearing on the analytic epidemiology.
Pregunta 176
Pregunta
A malfunctioning space heater was used each time the outside temperature dropped below freezing
Pregunta 177
Pregunta
At the Eclipse Restaurant, sodium nitrite was mistaken for table salt in the preparation of breakfast one morning only
Pregunta 178
Pregunta
Common cold passed from classmate to classmate
Pregunta 179
Pregunta
A group of tourists on a weeklong bus tour of a European country experienced an outbreak of norovirus. The group had followed a consistent meal time pattern: each morning they had breakfast together in whichever hotel they had stayed from 6:00 a.m. to 7:00 a.m., stopped for lunch from 1:00 p.m. to 2:00 p.m., then had dinner together either at the next hotel or at a restaurant at about 7:00 p.m. The incubation period for norovirus is about 24-48 hours, with a median of about 33 hours. On which day and at which meal was exposure most likely?
Respuesta
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April 19 Dinner
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April 20 Breakfast
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April 20 Lunch
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April 20 Dinner
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April 21 Breakfast
Pregunta 180
Pregunta
Possible explanations for a case that occurs substantially later than the other cases in an outbreak include:
Respuesta
-
Similar but unrelated disease
-
Secondary case
-
Case with unusually long incubation period
-
Time of exposure later than others
-
Error in recording date
-
All of the above
-
None of the above
Pregunta 181
Pregunta
A spot map is particularly useful for displaying:
Respuesta
-
Geographic location of exposure of each case-patient
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Residence of each case-patient
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Incidence rate of disease by area
-
Prevalence rate of disease by area
Pregunta 182
Pregunta
Which of the following may be useful in generating hypotheses in an outbreak setting?
Respuesta
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Review the literature
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Look at the descriptive epidemiology
-
Look at the outliers
-
Talk with the local health authorities
-
Talk with a few of the case-patients
-
Talk with subject matter experts
-
All of the above
-
None of the above
Pregunta 183
Pregunta
The key feature of an analytic (epidemiologic) study is
Respuesta
-
Analysis by time, place, and person
-
Calculation of a risk ratio or odds ratio
-
Use of Epi Info to analyze the data
-
Presence of a comparison group
Pregunta 184
Pregunta
Disease control measures can be directed at the:
Respuesta
-
Agent
-
Source
-
Mode of transmission
-
Portal of entry
-
Host susceptibility
-
All of the above
-
None of the above
Pregunta 185
Pregunta
Use the information in the following paragraph and data in the table for Questions 185–188.
An outbreak of gastrointestinal disease occurred 24-36 hours after people had attended a wedding. Of the 203 attendees (including the bride and groom), 200 completed questionnaires, and 50 reported illness compatible with the case definition. Tabulated food consumption histories are presented in the table below.
Ate Specified Food Did Not Eat Specified Food
Food Item Ill Well Total Ill Well Total
Punch 46 (25%) 138 184 4 (25%) 12 16
Wedding Cake 45 (45%) 55 100 5 (5%) 95 100
Sushi 10 (91%) 1 11 40 (21%) 149 189
What is the following study?
Respuesta
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Case Control
-
Cohort
-
Cross Sectional
-
Randomized Control Trial
Pregunta 186
Pregunta
The most appropriate measure of association for these data is the:
Pregunta 187
Pregunta
Which food is the most likely culprit?
Pregunta 188
Pregunta
Results of this outbreak investigation should be communicated to EXEPT: