Week 1 Epidemiology Quizzes
· Which of the following were driving factors in the past history of epidemiology? o The desire to increase the standard of living o The desire to understand frightening natural phenomena o The desire to provide better occupational conditions o The desire to find other explanation of witchcraft
All
1. A spurious association may be due to which of the following? a. Insufficient control of confounders b. Use of the wrong statistical methods c. Bias d. All of the above
All of the above
Which of the following best relates to equipoise? a. Use of a sham treatment that appears identical to the real treatment but lacks the treatment's active agent b. An uncertainty about the benefits/harms of the possible treatments or exposures c. Analysis of subjects according to their randomized treatment, regardless of whether they actually got or took the treatment d. Whether or not participants follow the treatment recommendation of the study
An uncertainty about the benefits/harms of the possible treatments or exposures
Interpret the meaning of one study's reported odds ratio of 1.6 (95% CI 1.1, 3.4) for the association between high level of fish oil consumption and prostate cancer. a. Cases are statistically significantly more likely than controls to have a high level of consumption of fish oil b. Fish oil is protective against prostate cancer c. Cases are more likely than controls to have a high level of a consumption of fish oil, but it is not statistically significant d. There is no association btwn fish oil intake and prostate cancer
Cases are statistically significantly more likely than controls to have a high level of consumption of fish oil
Which of the following study designs is sometimes referred to as a "snapshot in time"? a. Intervention study b. Cross-sectional study c. Cohort study d. Case-control study e. Time to treat study
Cross-sectional study
1. Which of the following is true about a ratio measure that is less than 1.0? a. There is a large assoc btwn the exposure and the health outcome b. There is an inverse assoc btwn the exposure and the health outcome c. There is no assoc btwn the exposure and the health outcome d. There is a possible causal assoc btwn the exposure and health outcome
There is a possible causal assoc btwn the exposure and health outcome
Which of the following is true about a ratio measure is greater than 1.0? a. There is a large assoc btwn the exposure and the health outcome b. There is an inverse assoc btwn the exposure and the health outcome c. There is no assoc btwn the exposure and the health outcome d. There is a possible causal assoc btwn the exposure and health outcome
There is a possible causal assoc btwn the exposure and health outcome
1. Interpret the meaning of an odds ratio of 1.00 for the association between consumption of fish oil and prostate cancer. a. Fish oil is protective against prostate cancer b. There is no association btwn fish oil intake and prostate cancer c. Cases are more likely than controls to have a high level of consumption of fish oil
There is no association btwn fish oil intake and prostate cancer
Which of the following is true about a ratio measure that equals 1.0? a. There is a direct association btwn the exposure and the health outcome b. There is an invasive association btwn the exposure and the health outcome c. There is no association btwn the exposure and the health outcome d. There is a small association btwn the exposure and the health outcome
There is no association btwn the exposure and the health outcome
Which of the following is true about a difference measure that is less than 0? a. There is no assoc btwn the exposure and health outcome b. There is a large assoc btwn the exposure and health outcome c. There is a positive assoc btwn the exposure and the health outcome d. There is possible protective assoc btwn the exposure and the health outcome
There is possible protective assoc btwn the exposure and the health outcome
Aggregate level data provide information on which of the following? (You must choose all that apply to receive credit for this question; no partial credit will be awarded.) a. The ability to link exposures and other risk factors who become diseased and those who did not b. The average exposure of the group, but not the individuals c. Exposures of each person d. The health outcome rate of the group, but we don't know exposures of individuals who become disease and those who do not
b. The average exposure of the group, but not the individuals d. The health outcome rate of the group, but we don't know exposures of individuals who become disease and those who do not
The statement "there is a threshold effect" best refers to which of the following? a. Temporality b. Plausibility c. Specificity d. Consistency e. Biological gradient
biological gradient
The statement "the results fit with other knowledge" best refers to which of the following? a. Biological gradient b. Coherence c. Plausibility d. Temporality e. Specificity
coherence
The statement "a number of studies by different investigators at various times using different methods in different populations show similar results" best refers to which of the following? a. Specificity b. Plausibility c. Biological gradient d. Consistency
consistency
`Which of the following studies is best described in this statement: "A study where the participants receive one drug for heart disease and then later receive a different drug for heart disease." a. Randomized control trial b. Case-control trial c. Cross over clinical trial d. Intervention study e. Cohort study
cross over clinical trial
Which of the following conclusions to explain the hypothetical statement that "Air pollution is higher in New York City than in Washington D.C., but mortality from lung disease is lower in New York City than in Washington D.C." would be an example of ecologic fallacy? a. People in NYC may have better health insurance than people in DC b. Persons dying of lung disease in DC may have moved from high air pollution cities c. NYC may provide better tx for lung dz than DC d. Air pollution protects against lung disease deaths
d. Air pollution protects against lung disease deaths
True or False: It is always ethical to randomly have the investigator assign exposures to study participants in experimental studies.
false
True or False: The denominator for a measure of occurrence in a cohort study is always person-time since the study participants are followed through time
false
True or False: The denominator of a risk is not fixed by the "at-risk" population size at the beginning of a study observation period
false
· Which of the following is the best description of the second epidemiologic transition from major epidemics to endemic disease? o A transition from high morality to lower mortality o A transition from chronic disease to more infectious disease o A period when newly emerging disease appeared frequently o A period when human immune systems adapted and changed o An increase in zoonotic disease and increased encounters with disease vectors
o A period when human immune systems adapted and changed
· Which of the following are true about the cholera epidemic of 1854? o Approximately 600 people died by the end of the epidemic o This cholera epidemic affected people throughout Europe o A water pump in London was implicated as being the source of the epidemic o Sir Edwin Chadwick contributed to discovering the cause of the epidemic o John Snow contributed to discovery cause
o Approximately 600 people died by the end of the epidemic o A water pump in London was implicated as being the source of the epidemic o John Snow contributed to discovery cause
In order to calculate a risk, which of the following steps must be taken? (You must choose all that apply to receive credit for this question o Determine how many people in the study were exposed or unexposed to the exposure under study o Define the at-risk study population o Determine the number of new cases of the outcome under study o define a case definition for the health outcome under study o determine the number of males and females in the study
o Define the at-risk study population o Determine the number of new cases of the outcome under study o define a case definition for the health outcome under study
· Which of the following is the best definition of an epidemiologic transition to fill in the blank: An epidemiologic transition _______ o Describes changing patterns of population age distributions, mortality, fertility, life expectancy, and causes of death o Describes a transition from high mortality to lower mortality o Refers to change in how epidemiologists are trained o Describes changing patterns of individual age distributions, mortality, fertility, life expectancy, and causes of death
o Describes changing patterns of population age distributions, mortality, fertility, life expectancy, and causes of death
· The epidemiologic transition of Hunter-gatherer to cities is related to which event? o Resurgence of infectious diseases o From few epidemics to major epidemics o From a focus on individual health to population health o From major epidemics to endemic disease o From infectious to non-infectious diseases o From a focus on occupational health to environmental health
o From few epidemics to major epidemics
If you are studying the rate of leukemia, which of the following events would affect a participant's person-time? (You must choose all that apply to receive credit for this question; no partial credit will be awarded.) o Participant decides to long longer participate in study o Death o Being sick with influenza o Loss to follow-up Participant goes out of town for a weekend
o Participant decides to long longer participate in study o Death loss to follow-up
If you are studying the rate of breast cancer, which of the following events would affect a participant's person-time? (You must choose all that apply to receive credit for this question; no partial credit will be awarded.) o Participant decides to long longer participate in study o Death o Loss to follow-up o Diagnosis with uterine cancer o pt undergoes a double mastectomy
o Participant decides to long longer participate in study o Death o Loss to follow-up o pt undergoes a double mastectomy
1Which of the following are acceptable ways to express "person-time"? (You must choose all that apply to receive credit for this question; no partial credit will be awarded.) o Person-months o Person-years o Person-days o Person-minutes
o Person-months o Person-years o Person-days o Person-minutes
True or False: Causal relationships provide interesting information to epidemiologists but are rarely used to make public health decisions and design interventions.
False
True or false: It is best to use a difference measure when trying to understand the cause or etiology of a health outcome or disease.
Fasle
Subjects are selected into case-control studies based on their: a. Exposure status b. Health outcome or disease status c. Health outcome and exposure status
Health outcome or disease status
True or False: Failing to meet one or more of the 9 Bradford-Hill criteria means that the studied relationship should not be considered causal.
False
True or False: The Bradford-Hill criteria were originally developed to answer the question of whether cigarettes cause disease, especially lung cancer.
True
True or False: The season can be a good epidemiologic measure of time.
True
True or False: There are nearly always some genetic and some environmental causes in every causal mechanism.
True
True or false: A difference measure treats the prevalence, risk or rate of the health outcome among the unexposed group as a "background" prevalence, risk or rate.
True
True or false: The null value used when interpreting a difference measure is 0.
True
True or false: The term "relative risk" is sometimes used to refer to any of the ratio measures of association.
True
True or false: When a ratio measure is greater than 1 it means the prevalence, risk or rate in the exposed is greater than in the unexposed group.
True
· True or False: Qualitative data deals with narrative descriptions and quantitative data deals with measurements.
True
True or False: Hospital controls would be a good choice of control group to accurately represent the source population of prostate cancer cases for a study of the effect of fish oil consumption and prostate cancer.
False
True or False: If an exposure proceeds a health outcome and is strongly associated with that health outcome, we can then say that without a doubt that the observed association is causal.
False
True or False: In a case-control study it is possible to sample on exposure status
False
True or False: The 9 Bradford-Hill criteria should be used as a check list to determine if a causal relationship exists.
False
True or False: The Bradford-Hill criteria were originally developed to answer the question of whether bacteria caused tuberculosis
False
True or False: The ecological fallacy is when you conclude that an association between exposure and the health outcome at individual level is true at group level when this may not be true.
False
True or False: The formula for a rate is the number of existing cases of the disease outcome divided by the number of people studied, with a mention of the time period under observation
False
True or false: A ratio measure of association expresses the prevalence, risk or rate among exposed in excess of that among the unexposed or less-exposed.
False
True or false: The term "relative risk" is the most precise term to use when discussing measures of association.
False
True or false: When a ratio measure is less than 1 it means the prevalence, risk or rate in the exposed is greater than in the unexposed group.
False
True or false: both a prevalence ratio and a prevalence difference are considered measures of occurrence.
False
True or false: both a risk ratio and a risk difference are considered measures of disease occurrence.
False
1. T or F: the term incidence is used to refer to prevalence, risks, and rates
F
Which of the following are ratio measures used in epidemiology? (You must choose all that apply to receive credit for this question; no partial credit will be awarded.) a. Risk ratio b. Odds ratio c. Rate ratio d. Occurrence ratio e. Prevalence ratio
Occurrence ratio
Which of the following measures is sometimes used because of its convenient mathematical properties? o Rate o Prevalence o Odds o Risk
Odds
· Which of the following is NOT an epidemiologic measure of person? o Genetic factors o diet o Physical location o Living conditions o Education level
Physical location
Which of the following measures of occurrence are used for cross-sectional studies? (You must choose all that apply to receive credit for this question; no partial credit will be awarded.) · Risk · Time · Prevalence · Rate · Odds
Prevalence
Which of the following studies is best described in this statement: "A study where the effectiveness of 2 different diabetes drugs are compared." a. Randomized control trial b. Case-control study c. Cross-over clinical trial d. Intervention study e. Cohort study
Randomized control trial
Which of the following study designs is the most persuasive in establishing causality? a. Ecologic studies b. Cohort studies c. Randomized controlled trials d. Case-control studies
Randomized controlled trials
Which of the following measure(s) is/are able to capture the reality of a dynamic population? (You must choose all that apply to receive credit for this question; no partial credit will be awarded.) o odds o Rate o Risk o Prevalence
Rate
The 9 factors used as a guideline for determining causality are referred to as:
The Bradford-Hill Criteria
Interpret the meaning of one study's reported rate ratio of 0.5 (95% CI 0.2, 0.9) for the association between high level of Vitamin D consumption and breast cancer incidence a. High vitamin D consumption is assoc with an increased breast cancer rate b. There is no assoc btwn high vitamin D consumption and breast cancer rates c. Those who consume a high level of vitamin D are less likely than those who consume little or no Vitamin D, to have a high rate of breast cancer incidence, but it is not statistically significant d. Those who consume high level of vit D are statistically significantly less likely that those who consume low or no Vit D, to have high rate of breast cancer incidence
Those who consume high level of vit D are statistically significantly less likely that those who consume low or no Vit D, to have high rate of breast cancer incidence
The 9 Bradford-Hill criteria should be used as a guideline to consider if a causal relationship exists.
True
True or False: Some diseases or health outcomes do not display a dose-response relationship with a causal exposure.
True
Which of the following are possible uses of cross-sectional study results? (You must choose all that apply to receive credit for this question; no partial credit will be awarded.) a. Evaluate the proportion of a population with the health outcome or risk factor of interest b. Evaluate the risk of a population with the health outcome or risk factor of interest c. Study a chronic health outcome lacking information on time of onset. d. Help with developing surveillance programs. e. Help with planning or administering preventative or health care services.
a. Evaluate the proportion of a population with the health outcome or risk factor of interest c. Study a chronic health outcome lacking information on time of onset. d. Help with developing surveillance programs. e. Help with planning or administering preventative or health care services.
Which of the following are disadvantages of cohort studies? (You must choose all that apply to receive credit for this question; no partial credit will be awarded.) a. Loss to follow-up b. Time-consuming to conduct c. Expensive d. Inefficient for rare outcomes e. Good for studying single outcomes only
a. Loss to follow-up b. Time-consuming to conduct c. Expensive d. Inefficient for rare outcomes
The study population in a cohort study can be which of the following? (You must choose all that apply to receive credit for this question; no partial credit will be awarded.) a. Open b. Very large c. Closed d. Dynamic change
a. Open b. Very large c. Closed d. Dynamic change
Which of the following are ways in which cross-sectional studies can be used / conducted? (You must choose all that apply to receive credit for this question; no partial credit will be awarded.) a. Study a population at a point in time b. Study a population over a defined period of time c. Characterize data on prevalence of an exposure as well as a health outcome d. Only characterize the prevalence of a health outcome
a. Study a population at a point in time C. Characterize data on prevalence of an exposure as well as a health outcome D. Only characterize the prevalence of a health outcome
Prostate cancer occurs mainly in older men. About 6 cases in 10 are diagnosed in men aged 65 or older, and it is rare before age 40. The average age at the time of diagnosis is about 67. A case control study is conducted to determine the effect of fish oil consumption on prostate cancer in the state of Colorado. Which of the following would be an appropriate source population for this study? a. The entire population of men in Colorado over the age of 50 b. The entire population of Colorado c. The entire population of men in Colorado
a. The entire population of men in Colorado over the age of 50
A cohort may be defined based on which of the following? (You must choose all that apply to receive credit for this question; no partial credit will be awarded.) a. Behavioral characteristics b. Geography c. Race d. Gender e. Age
all
The denominator of a rate is affected by which of the following? o Births o Migration o Deaths o loss to follow-up o study drop-outs
all
Which of the following are advantages of using a rate measure? (You must choose all that apply to receive credit for this question (no partial credit will be awarded.) o Good for health outcomes or diseases with long latent periods o Good for health outcomes or diseases that are of long duration o Suitable for a dynamic population o Can accommodate repeated events that affect the same study participant o Flexibility
all
Which of the following types of events can be measured by a risk and/or a rate? o Newly developed cases of disease o Development of a drug or tx SE o Recurrence of sz o All of the above
all of the above
Which of the following are advantages of ecologic studies? (You must choose all that apply to receive credit for this question; no partial credit will be awarded.) a. Individual-level data on exposure and health outcomes are often publicly available in state and national data bases b. Convenience c. Low cost d. Help conservationists understand ecological principles e. Useful for evaluating impact of community-level interventions
b. Convenience c. Low cost e. Useful for evaluating impact of community-level interventions
1. What is the primary difference between risk and prevalence? o Risk describes the number of diseasesed persons present in the population divided by the number of persons in the population during a specified time period, whereas prevalence describes the number of newly diseased person present in the population in a specified time period divided by the number of at-risk persons in the population o Prevalence describe the number of diseased persons present in the population in a specified time period whereas risk describes the number of people who die from disease in the population in a specified time period o Prevalence describe the number of diseased persons present in the population divided by the number of persons in the population in a specified time period, whereas Risk describes the number of newly diseased person present in the population divided by total at risk persons in the population in a specified time period
o Prevalence describe the number of diseased persons present in the population divided by the number of persons in the population in a specified time period, whereas Risk describes the number of newly diseased person present in the population divided by total at risk persons in the population in a specified time period
· Which of the following are part of epidemiology (choose all that apply)? o The study of the factors that determine whether someone gets a particular health outcome o The study of the natural history of health outcomes o Provision of health care to people with diseases o The study of the distribution of health outcomes, risk factors, and exposures in populations
o The study of the factors that determine whether someone gets a particular health outcome o The study of the natural history of health outcomes o The study of the distribution of health outcomes, risk factors, and exposures in populations
If you are studying the rate of relapse for lung cancer after treatment, which of the following events would affect a participant's person-time? (You must choose all that apply to receive credit for this question; no partial credit will be awarded.) o Time period(s) when pt is considered to have active lung cancer o Participant decides to no longer participate o Time period(s) when pt is in remission o Time of initial diagnosis with lung cancer
o Time period(s) when pt is considered to have active lung cancer o Participant decides to no longer participate o Time period(s) when pt is in remission
Once the study population has been defined, the denominator of a risk is affected by which of the following? (You must choose all that apply to receive credit for this question; no partial credit will be awarded.) o Who is at risk of developing the health outcome o Loss to follow-up o Births o Migration o Deaths
o Who is at risk of developing the health outcome
The statement "the biologic mechanism is known" best refers to which of the following? a. Temporality b. Biological gradient c. Plausibility d. Specificity e. Consistency
plasuability
Which of the following is generally considered the weakest guideline? a. Consistency b. Biological gradient c. Specificity d. Plausibility
specificty
The statement "exposure to factor of interest precedes the outcome" best refers to which of the following? a. Consistency b. Specificity c. Temporality d. Biological gradient e. Plausibility
temporality
Which of the following is generally considered to be the strongest or most important guideline? a. Plausibility b. Consistency c. Specificity d. Temporality e. Biological gradient
temporarily
