BBH 440 Final exam
Which of the following p-values would generally be considered statistically significant? .03 .091 .06 .50
.03
Which of the following odds ratios would be considered statistically significant? 3.8 (3.1-4.1) 8.9 (.55-10) .42 (.33-1.5) 1.4 (.89-1.9)
3.8 (3.1-4.1)
What percent change is indicated by an odds ratio of .92? 92% 80% 9.2% 8%
8%
What percent change is indicated by a relative risk of 1.95? 85% increase 195% increase 95% decrease 95% increase
95% increase
An organization solicits statistics on the number of diagnosed cases of prostate cancer by contacting hospitals throughout the country and asking for their data on prostate cancer cases. This is what type of surveillance? Active Passive
Active
A research group is interested in studying the relationship between stress in social relationships and depressive episodes. They find a group of people who have had a depressive episode and ask them whether they experienced significant social stress in the week before their episode began. they also ask them if they experiences significant social stress in another 1-week period sometime the month before (when they didn't have a depressive episode). this is what type of study? Case-crossover study nested case-control study prospective cohort study retrospective cohort study
Case-crossover study
The water supply for a town is contaminated with e. coli, causing an outbreak of illness. This is what type of epidemic? Common source Propagated
Common source
Researchers conduct a cohort study of the relationship between daily alcohol consumption and motor vehicle accidents and find the relative risk of getting in an accident for alcohol drinkers compared to non-drinkers is 4.5 with a confidence interval of 3.2-6.9. This suggests that: There is no significant association between daily alcohol consumption and motor vehicle accidents Daily alcohol consumption is associated with an increased risk of motor vehicle accidents Daily alcohol consumption is associated with a reduced risk of motor vehicle accidents.
Daily alcohol consumption is associated with an increased risk of motor vehicle accidents
In the second half of the twentieth century, mortality rates due to cardiovascular disease have: Declined on average Increased on average Remained about the same Fluctuated--- declining about 1970 and then increasing until the present day
Declined on average
A/an ___________ is a blood clot that is from its site of origin and can block a blood vessel at a site distant from its site of origin. Thrombus Infarction Embolus Plaque rupture
Embolus
To be classified as an epidemic, an outbreak must affect a large number of people. True False
False
In general, which of the following cancer stages has the worst prognosis? 0 I III IV
IV
To calculate attributable risk difference with a sample, what statistic is subtracted from the incidence in the exposed group? Incidence in both the exposed and unexposed groups Incidence in unexposed group Incidence in the total population the sample was drawn from Incidence in the exposed group
Incidence in unexposed group
Amber walks into a classroom without realizing that a student had sneezed as he walked out 10 minutes earlier and expelled viral particles that remained in the air, floating on dust particles. Amber walks through this "cloud" of viral particles and becomes sick 3 days later. What type of transmission is this? Indirect - vector-borne Direct - host-to-susceptible host contact Direct - droplet spread Indirect - airborne
Indirect - airborne
_______ specifically refers to a restriction in blood supply to a tissue. Thrombus Infarction Ischemia Embolus
Ischemia
An outbreak occurs where the first case is detected on January 15th and the last case is detected on January 27th. The average incubation period for the disease is 7 days with a range of 4-10 days. What is the probable period of exposure? January 8-20 January 11-23 January 11-17 January 17-23
January 11-17
A disease outbreak occurs and the peak number of cases is on January 27th. The average incubation period for the pathogen that caused the outbreak is 12 days with a range of 10-14 days. What is the probable date of common exposure? January 17 January 13 January 15 January 24
January 15
A screening tool helps lead to diagnosis of cancer 1 year earlier than the onset of clinical symptoms. However, this diagnosis doesn't lead to an overall increase in longevity. If the 1-year difference in time of diagnosis is included in survival time when assessing the value of the screening tool, what type of bias is occurring? Overdiagnosis bias Selection bias Lead time bias Length bias
Lead time bias
A study is conducted that involves surveying participants about their diet, exercise level, and weight early in the year and then following up with them and again asking about their diet, exercise level, and weight in December of the same year. Is this a cross-sectional study? yes no
No
An organization provides a phone number and website that individuals can use to voluntarily report any allergic reactions they experience after using cosmetic products. This is what type of surveillance? Active Passive
Passive
Patient #1 has a total cholesterol of 200 and HDL of 50. Patient #2 has a total cholesterol of 210 and HDL of 70. Based on these numbers alone, which patient seems to have a higher risk of cardiovascular disease? Patient #1 Patient #2 Their risk is equivalent
Patient #1
Publication bias tends to occur because studies that have _________ results are more likely to be published. Positive Negative
Positive
Population attributable risk percent can be calculated using incidence rates or, if these are not known, it can be calculated with these two statistics: Prevalence of the outcome and relative risk Prevalence of the exposure and relative risk Prevalence of the outcome and odds ratio Prevalence of the exposure and odds ratio
Prevalence of the exposure and relative risk
What statistics compares the incidence density rate in the exposed to the incidence density rate in the unexposed. rate ratio correlation odds ratio relative risk
Rate ratio
A 5-year survival rate refers to: the proportion of patients who are still receiving treatment 5 years after cancer diagnosis the proportion of patients who are cancer-free 5 years after cancer diagnosis The proportion of patients who are still alive 5 years after cancer diagnosis the proportion of patients who are still alive 5 years after the environmental exposure that caused them to develop cancer
The proportion of patients who are still alive 5 years after cancer diagnosis
In assessing a screening test, a researcher calculates a likelihood positive likelihood ratio of 14. This suggests that: There is a very good chance that someone who receives a positive result on the test does not actually have the disease There is a very good chance that someone who receives a positive result on the test does actually have the disease There is a very good chance that someone who receives a negative result on the test does actually have the disease There is a very good chance that someone who receives a negative result on the test does not actually have the disease
There is a very good chance that someone who receives a positive result on the test does actually have the disease
An individual is screened for disease A and the screening test comes back negative. A subsequent diagnostic test finds they do not actually have the disease. The initial screening test is an example of a: True negative True positive False positive False negative
True negative
most of the diabetes cases in the world are of what type of diabetes? Type 1 Type 2
Type 2
In an experiment it is found that the odds ratio for a particular exposure and a disease is .48, and it is significant. This suggests that: a. the exposure is associated with a decreased probability of having the disease b. the exposure is not associated with an increased or decreased probability of having the disease c. the exposure is associated with increased probability of having the disease
a. the exposure is associated with a decreased probability of having the disease
A researcher wants to compare the overall mortality rates in Africa to those in the United States. She should use a/an: incidence-density rate cause-specific mortality rate crude mortality rate adjusted mortality rate
adjusted mortality rate
A pandemic is more likely to occur as a result of: antigenic shift antigenic drift
antigenic shift
In the direct method of age adjustment, after selecting a reference population the next step is to: a. find the total number of expected cases and divide by the total size of the reference population b. apply age-specific rates from the reference population to study population A c. apply age-specific rates from study population A to the reference population d. divide the crude mortality rates of each study population by the crude mortality rate of the reference population
apply age-specific rates from study population A to the reference population
Steve gets a flu shot that contains inactivated/killed flu virus. What type of immunity does this create? natural - passive artificial - active natural - active artificial - passive
artificial - active
Researchers conduct a study and find that the attributable risk percent for high workplace stress and insomnia is 14%. This suggests that: a. 14% of people with insomnia also have high workplace stress b. 14% of the insomnia cases in those with high workplace stress are likely due to that stress c. 14% of people with high workplace stress are likely experiencing that stress in part due to tiredness from insomnia d. 14% of people with high workplace stress have insomnia
b. 14% of the insomnia cases in those with high workplace stress are likely due to that stress
If the standardized mortality ratio is greater than 1, it suggests: a. something is causing mortality rates in the reference population to be higher than we would expect based on the mortality rates seen in the study population b. something is causing mortality rates in the study population to be higher than we would expect based on the mortality rates seen in the reference population c. something is causing mortality rates in the study population to be lower than we would expect based on the mortality rates seen in the reference population
b. something is causing mortality rates in the study population to be higher than we would expect based on the mortality rates seen in the reference population
Patterns of mortality during the 1918 Spanish flu were unusual in that: a. death rates among all age groups were equivalent b. there were high rates of death in young adults, which aren't usually impacted severely during flu outbreaks c. there were very few deaths among young adults, which usually are impacted severely during flu outbreaks d. the elderly seemed to be immune to the effects of the virus, exhibiting almost no mortality
b. there were high rates of death in young adults, which aren't usually impacted severely during flu outbreaks
The Diabetes Prevention Program found that: Only a combination of behavioral change and metformin was successful in reducing the risk of type 2 diabetes behavioral change can be more effective than metformin in reducing the risk of type 2 diabetes metformin is more effective than behavioral change in reducing the risk of type 2 diabetes neither metformin, behavioral change, no a combination of the two was successful in reducing the risk of type 2 diabetes.
behavioral change can be more effective than metformin in reducing the risk of type 2 diabetes
Individuals are classified as pre-diabetic based on their: family history blood glucose levels weight race
blood glucose levels
Many of the major complications of diabetes are thought to start with the effect of. hyperglycemia on: fat cells neurons hormone levels blood vessels
blood vessels
A cohort study examines the relationship between caffeine consumption and high-normal blood pressure. It finds that daily caffeine consumption is associated with a statistically significant relative risk of high-normal blood pressure of 3.5. How would this statistic be interpreted? a. Individuals who consumed caffeine daily had a blood pressure reading that was about 3.5 times higher than those who did not consume caffeine daily b. Individuals who consumed caffeine daily developed high-normal blood pressure 3.5 times more quickly than those who did not consume caffeine daily c. Individuals who consumed caffeine daily were 3.5 times more likely to develop high-normal blood pressure than those who did not consume caffeine daily d. Individuals who consumed caffeine daily were 3.5 times more likely to regularly get their blood pressure checked
c. Individuals who consumed caffeine daily were 3.5 times more likely to develop high-normal blood pressure than those who did not consume caffeine daily
A researcher is interested in studying the relationship between alcohol intake and type 2 diabetes. Out of a sample of 500 people, she forms one group consisting of people who have type 2 diabetes and another consisting of people who don't. Then she gathers information about their alcohol intake. This is what type of study? ecological study case study case-control study cohort study
case-control study
Researchers want to investigate the link between Cotard's delusion, an extremely rare mental disorder where a person comes to believe they are dead, and previous psychiatric disturbances. Which study would be better suited to investigate this? Cohort study case-control study
case-control study
A researcher wants to know how many people died of colon cancer in the United States last year. He would calculate a/an: infant mortality rate cause-specific death rate crude mortality rate age-specific death rate
cause-specific death rate
A group of researchers are investigating the relationship between shoe size and reading ability in a sample of students that range in age from 6-14. They find a positive correlation between shoe size and reading ability and conclude that shoe size is casually related to reading ability. Which error of causation best describes this hypothesized relationship? Reverse causation common casual variable coincidence
common casual variable
A researcher wants to test the effectiveness of billboards in reducing alcohol consumption. She chooses two cities and gets statistics on alcohol sales for a 3-month period. Then she puts anti-alcohol billboards up in one city (but not the other) for 3 months. Finally, she compares statistics on alcohol sales again after the intervention. This is what type of study? retrospective cohort study clinical trial community trial case-control study
community trial
James has been sick with mononucleosis for the past couple of weeks but finally is recovering and no longer has any overt symptoms. He is, however, still contagious and capable of affecting others. What type of carrier is James? incubatory carrier convalescent carrier healthy (passive) carrier
convalescent carrier
The number of new cases per year of a disease has not changed, but a drug-resistant strain of the bacteria that causes the disease has led to significant increases in the number of deaths due to the disease. These changes will likely cause the prevalence rate to: decrease increase
decrease
A researcher conducts a survey that is used to find the prevalence of smoking in the United States. Based on this information alone, this is what type of research: analytic descriptive
descriptive
Stacey is infected with herpes simplex virus after kissing Todd, who has the disease. What type of transmission is this? direct - host-to-susceptible host contact direct - droplet spread indirect - vehicle-borne indirect - airborne
direct - host-to-susceptible host contact
In a study, the participants and investigators are both unaware of what group (treatment vs. control) the participants have been assigned to. This is what level of blinding? single double triple quadruple
double
A researcher group obtains school district data on the number of students with intellectual disabilities and also obtains city data on the level of certain pollutants in the water supply. they find that the level of water pollutants is positively correlated with the number of students with intellectual disabilities. This is what type of study? ecological study passive surveillance study case study case series
ecological study
if a researcher wants to conduct a study that allows her to be able to say confidently that an exposure causes an outcome, what study design would she be advised to use: case-control experimental ecological case study
experimental
A cohort study is an experimental study, not an observational study true false
false
Screening tests are generally used as diagnostic tests for individuals who were previously unaware they had the disease. true false
false
The members of a community involved in a community trial must always be informed they are involved in an experiment true false
false
cross-sectional studies can be used to make and cause & effect interpretation about an exposure and an outcome true false
false
despite the rapid increase in diabetes prevalence in the US, it is still not one of the top-10 causes of death true false
false
the term "cancer" describes any tumor, whether the tumor is classified as benign or malignant. true false
false
An individual is screened for disease A and the screening test comes back positive. A subsequent diagnostic test finds they do not actually have the disease. The initial screening test is an example of a: True negative True positive False positive False negative
false positive
An agent is highly contagious; upon introduction to a population, it spreads rapidly throughout the population. However, it does not often cause serious illness and usually doesn't even cause any symptoms of disease. Which best describes the agent? high pathogenicity low infectivity high infectivity high virulence
high infectivity
Diabetes mellitus was named based on what symptoms present in diabetics? low urine output, high glucose levels in the urine high body weight, high glucose levels in the blood high urine output, high glucose levels in the urine increased desire to drink, high glucose levels in the saliva
high urine output, high glucose levels in the urine
If a relative risk is greater than 1, it means that the incidence in the exposed group is higher/lower than the incidence in the unexposed group. lower higher
higher
The most common form of cardiovascular disease is: rheumatic heart disease hypertension coronary artery disease congestive heart failure
hypertension
After a chemical spill, a number of workers spend various amounts of time working at the spill site to clean up. A researcher keeps track of the number of hours they spend working there, then after 6 months calculates the number of new cases of respiratory illness that have occurred in the workers out of the total number of hours spent working at the site (for all workers). This rate would be known as a/an: age-specific incidence rate incidence-density rate secondary attack rate incidence rate
incidence-density rate
Jimmy, a child infected with measles, is diagnosed after a doctor's visit and is the first recognized case in an outbreak that will eventually affect over 100 people. It is learned later that Jimmy actually contracted the disease from an unvaccinated child who had been infected with measles after traveling outside the country. Jimmy would be considered the: index case primary case
index case
If an individual is known to be sick, they would be _____________ from the healthy population; if they have been exposed to a pathogen but it is not yet known if they will get sick, they would be _______________. isolated; quarantined quarantined; isolated
isolated; quarantined
One reason to use likelihood ratios rather than predictive value is: Likelihood ratios are not influenced by the prevalence of the disease Predictive values can only be used in situations where sensitivity is relatively high Likelihood ratios can be calculated without knowing if positive test results were true or false positives Predictive values are more likely to be influenced by lead-time bias
likelihood ratios are not influenced by prevalence of the disease
Which of the following types of cancer is responsible for causing the most cancer deaths in men and women? lunch and bronchus colon and rectum pancreas melanoma
lunch and bronchus
Hannah has previously been infected with measles. When she is exposed to the measles virus again, her immune system recognizes it and prevents her from getting sick. What type of immunity is this? natural - passive artificial - passive natural - active artificial - active
natural - active
A group of researchers conduct a cohort study that examines the relationship between blood cholesterol levels and diabetes. At the end of the study, they decide to conduct an additional study to explore another hypothesis that a particular genetic background increases the risk of diabetes. They take a sample of participants who developed diabetes during their cohort study and a sample who did not, then they compare the likelihood of having a particular genetic background between both groups. this additional study is what type of study? case-crossover study retrospective cohort study prospective cohort study nested case-control study
nested case-control study
A group of participants are assigned to the treatment or control group based on whether their zip code ends in a 0-4 or a 6-9. Is this a truly random method of assignment? yes no
no
A research group conducts a study to examine the relationship between unemployment and drug use. they get unemployment numbers from state governments for 6 states and they obtain numbers regarding the number of drug arrests in those same 6 states. they find a positive correlation between unemployment and drug arrests. They. conclude that being unemployed makes it more likely someone will use and/or be arrested for drug use. Is the logic they used accurate? yes no
no
A researcher publishes a case series that describes 18 cases of a previously unknown disease. Based on the information in the case series, the author concludes that the disease is caused by excessive sun exposure. Disregarding any of the potential details of the case series, is the researcher able to make this conclussion? yes no
no
A research group is examining the relationship between long-term smoking (5+ years) and blood pressure. They recruit a group of long-term smokers and a group of non-smokers, then measure their blood pressure. What general experimental approach is this considered? observational experimental
observational
If a mortality rate decreases after age adjustment, it suggests the study population is __________ than the reference population. older younger
older
A new screening tool for a slowly-progressing disease is developed and is immediately used extensively, identifying a large number of disease cases. It is later learned, however, that many of the cases were identified at such a late age that the patients were unlikely to have experiences symptoms before dying of natural causes. This is an example of: lead time bias length bias over-diagnosis bias misclassification
over-diagnosis bias
Which of the following riskfactors is present in up to 90% of type 2 diabetes cases: smoking alcohol consumptions hypertension overweight and obesity
overweight and obesity
Insulin is produced primarily in the: brain thyroid liver pancreas
pancreas
A baby receives antibodies from his mother in the process of breastfeeding. What type of immunity is this? active - natural passive - artificial active - artificial passive - natural
passive - natural
A researcher conducts a survey in which it is asked, "Are you now suffering from depression or have you ever experienced an episode of depression in your life?" The morbidity rate that would be obtained if the researcher then calculated the total number of individuals who have experienced depression (now and in the past) out of the total group surveyed would be: point prevalence rate period prevalence rate
period prevalence rate
In this phase of the clinical trial process, a drug is tested on healthy subjects to asses safety and side effects phase I phase II phase III phase IV
phase I
It is found that 90/100 of the positive tests for a particular screening tool were true positives. 90% is the: positive likelihood ratio specificity positive predictive value sensitivity
positive predictive value
A group of researchers conducts a clinical trial using a group of participants who are at a high risk of developing type 2 diabetes. The study involves administering a drug that is supposed to reduce the likelihood one will develop type 2 diabetes. The long-term study identifies how many members of the experimental vs. control group develop the disease. This is what type of clinical trial preventative therapeutic
preventative
An epidemic that spreads only by one infected person transmitting the disease to another susceptible person would be called a: epizootic propagated epidemic common source epidemic mixed epidemic
propagated epidemic
Out of a group of 100 men, 22 are smokers. Thus, smokers make up 22% of the group. 22% would be considered a: rate proportion ratio
proportion
A research group is interested in studying the relationship between pesticide exposure and Alzheimer's disease. They identify a group of people who have had high levels of pesticide exposure and another who have had no pesticide exposure. They then follow-up with them every year for the next 25 years to see how many in each group develop cancer. This is what type of study? case-control study ecological study retrospective cohort study prospective cohort study
prospective cohort study
The population of State College is 41,757 and the number of automobiles registered to members of the population is 30,016. There are thus 30,016 cars to 41,757 people or .72 cars per person. This comparison is a: ratio proportion rate
ratio
When conducting a case-control study on the relationship between high carbohydrate levels in the diet and blood pressure, researchers ask participants to respond to a survey about the average daily carbohydrate levels in their diet over the past year. What type of bias is this question likely to be affected by? selection bias prevalence-incidence bias recall bias confirmation bias
recall bias
In 2017, a research group is interested in studying the relationship between exposure to a particular chemical and cancer. They identify a group of people who were exposed to the chemical during an industrial accident in 1985 and another group who were never exposed. Then they examine medical records to see if those in the exposed group were more likely to develop cancer over the 20 years following their exposure. This is what type of study? ecological study prospective cohort study retrospective cohort study case-control study
retrospective cohort study
In a sample of 1000 people who are screened, 100 actually have disease A. The screening tool identifies 85/100 of the diseased individuals as potential disease cases. 85% is a measurement of the screening tools: sensitivity specificity positive predictive value negative predictive value
sensitivity
In a sample of 1000 people who are screened, 100 actually have disease B. A screening tool identifies 700 of the 900 non-diseased individuals as being disease free. 78% (i.e. 700/900) is a measurement of the screening tool's: sensitivity specificity positive predictive value negative predictive value
specifity
Colon cancer screening is recommended periodically for men and women over age 50; the goal of this type of screening is to detect colon cancer in its early stages, before the patient is aware they have it. This type of screening is aimed at detecting disease in what stage: stage of susceptibility stage of subclinical disease stage of clinical disease stage of recovery, disability, or death
stage of subclinical disease
Which of the following cancers is generally considered to be a "bad" cancer based on 5-year survival rates thyroid breast stomach melanoma
stomach
If a funnel plot does NOT indicate publication bias, it should appear: symmetrical and circular symmetrical and triangular in shape, with more variability in results among studies with smaller sample sizes asymmetrical, with more studies indicating positive effects than negative effects symmetrical and rectangular in shape, with similar variability in results among studies with small and large sample size sizes
symmetrical and triangular in shape, with more variability in results among studies with smaller sample sizes
A forest plot provides a graphical display of: The sample sizes of a collection of studies on a particular topic The overall results of a collection of studies on a particular topic The total number of studies published on a particular topic Whether or not the available studies in a particular area have been influenced by publication bias
the overall results of a collection of studies on a particular topic
Herd immunity refers to: a. the average number of secondary infectious cases produced by a single cases in a susceptible population b. acquired immunity in non-human animals c. groups that make decisions about vaccinations based on social influences, rather than medical advice d. the resistance of a population to an infectious disease, based on the number of individuals in the population who have immunity
the resistance of a population to an infectious disease, based on the number of individuals in the population who have immunity
Some agents are capable of producing toxins or poisons that can be harmful to a host. This term used to describe this quality is: immunogenicity toxigenicity infectivity resistance
toxigenicity
Type 2 diabetes can be considered a pandemic true false
true
_______ is generally characterized by insulin deficiency, while _______ is generally characterized by insulin resistance. type 1 diabetes, type 2 diabetes type 2 diabetes, type 1 diabetes type 1 diabetes, type 1 diabetes type 2 diabetes, gestational diabetes
type 1 diabetes, type 2 diabestes
If an agent has a high case-fatality ratio, it is said to have high: infectivity resistance virulence immunogenicity
virulence