HLPR222 Final Exam Question Set

Match the following types of preventions to their correct example (s) 1. Primary Prevention 2. Secondary Prevention 3. Tertiary Prevention B. Physical therapy A. Screening C. Vaccination D. Healthy Eating

1 = C and D 2 = A 3 = B

what are the advantages of cohort studies a.) Good for studying rare conditions or diseases, can simultaneously look at multiple risk factors. b.) rare exposures, can examine multiple effects of single exposure, clear temporal sequence c.) detailed description of disease occurrence in a single person d.) negative association between the exposure and outcome

B.)

Which of the following is a descriptive study design? a.) Ecologic study b.) Cross sectional study c.) Cohort study d.) Case control study

B.) All of the other options are analytic studies.

Which type of study uses the group rather than the individual as the unit of analysis? A.) Case Control Studies B.) Ecologic Studies C.) Cohort Studies D.) Randomized Control Trials

B.) The answer is B because out of all of these options, ecologic studies are the only ones that explore associations at the group level and these studies are often used when individual level data are unavailable.

Abnormal levels across a wide area, usually the globe describe which of the following levels of disease occurrence? a) Endemic b) Pandemic c) Epidemic d) Outbreak

B.) Pandemic is the correct answer because it occurs in a very wide area (worldwide), affecting a large number of people. This means that they are abnormal levels.

Which of the following are NOT included in the 4 components of a randomized controlled trial (RCT)? a) gather a similar study sample b) preassign study conditions, either for the intervention or the control groups c) create masking or blinding to prevent any type of bias d) compare measurements of outcomes between the intervention and control groups

B.) because the study conditions are not preassigned, they are randomized, hence the name randomized controlled trial (RCT). The other options however are true

Which measure of association is suitable for a Case Control study? A. Relative Risk B. Cohort C. Odds Ratio D. Randomized Control Trial (RCT) E. Both A & D

C.) Odds ratio is the measure of association suitable for a Case Control study because the attributes involved are: good for rare outcomes, begins with an outcome assessment, and cannot be used to calculate incidence.

Which is NOT a potential source of bias? a.) loss to follow-up b.) random misclassification c.) being within the causal chain d.) nonrandom misclassification e.) errors in self report f.) None of the above

C.) There are 4 types of bias that fall under 2 categories of bias. Under selection bias is loss to follow-up and selection bias. Errors in self-report is an example of misclassification. Depending on the nature of the error, it might be random or nonrandom. Being within the causal chain is something that determines that a variable is not a confounder.

Which study designs can establish temporality? A.) Ecologic studies B.) Case control studies C.) Cohort studies D.) A, B, and C

C.) Cohort studies are able to show a temporal relationship between the exposure and disease. In other words, these studies are able to show causation, whereas the other studies listed can only determine correlation.

Which of the following best describes Secondary Prevention? a.) Secondary Prevention occurs after the condition has occurred b.) An example of secondary prevention is physical therapy c.) Secondary Prevention occurs during the development of the condition d.) A vaccination is an example of Secondary Prevention

C.) Secondary Prevention occurs while the disease/condition is developing, not before or after. Option A and B refer to Tertiary Prevention, while Option D refers to Primary Prevention.

Which of the following must be true in order for a cross-sectional study to be conducted? A) An exposure & an outcome measured at several points in time B) An exposure & an outcome measured in the past C) An exposure & outcome measured at the same time D) An exposure & outcome measured in the future

C.) For a cross sectional study to be conducted, an exposure & outcome must be measured as they exist in a defined population at one specific time.

Which is NOT correct about cohort studies? a) It tracks a group of individuals over time to observe the development of outcomes b) Individuals being observed share a common characteristic with each other c) It collects data from an observation at a single point in time d) It can be used to study rare exposures that can identify potential causal relationships between exposures and outcomes

C.) because that is describing a cross sectional study. a cross sectional study collects data from an observation at one single point in time while a cohort study tracks individuals over a set time period

Which of the following is FALSE regarding cohort studies? a.) Cohort studies are an example of an analytic study design. b.) They begin selection for Cohort Studies via an exposed and non-exposed group. c.) Cohort studies are recommended for rare exposures because of their efficiency. d.)Cohort studies are relatively inexpensive and do not take that much time to conduct.

D.) One of the weaknesses of cohort studies is that they are expensive and time-consuming. All of the remaining options are considered strengths for why cohort studies are conducted.

When creating a study to find an association between exposure and outcome what is the best way to deal with cofounding? a.) Random Assignment of exposure b.) Specificity c.) Surveillance d.) Stratification

a.) Random Assignment is the only way we can control all of the confounding variables

Which area of epidemiology is ecological studies? a) Statistical analysis b) Analytical epidemiology c) Intervention studies d)Descriptive epidemiology

b.) because analytical epidemiology takes a broad approach to data collected, which is what ecological studies do.

When identifying potential confounders, how do we know if the variable is associated with the exposure? a.) The OR between the confounder and exposure needs to equal 1 b.) The RR between the confounder and exposure needs to not equal 0 c.) The OR/RR between the confounder and exposure needs to not equal 1 d.) The OR/RR between the confounder and exposure needs to equal 1

c.) because and 2 only include one, but it has to be both the OR and RR. And it is not 4 because the OR/RR needs to not equal 1.

Which of the following is not a common confounding variable? a.) Age b.) Biological sex c.) Height d.) Smoking

c.) because: age, biological sex and smoking are all the most common confounding variables because many diseases are directly linked to each of them, but height is not a common cause of disease.

Which of the following could be a correct odds ratio interpretation? a.) People who regularly smoke cigarettes are 16 times more likely to have lung cancer as people who do not smoke cigarettes. b.) People who regularly smoke cigarettes are 16 times as likely to be newly diagnosed with lung cancer over a period of 5 years compared to people who do not smoke cigarettes. c.) People who regularly smoke cigarettes are 16 times as likely to be newly diagnosed with lung cancer as people who do not smoke cigarettes. d.) People who regularly smoke cigarettes are 16 times as likely to have lung cancer as people who do not smoke cigarettes.

d.) because an odds ratio interpretation compares the odds of observing an outcome between people who are exposed and people who are not exposed. The other options listed present variations with incorrect wording (i.e. "more likely to") or interpret the value as a relative risk, so the final option is the only odds ratio interpretation that is correct in its entirety.

2,400 people were followed for 20 years. 500 of those people smoked cigarettes. Over the 20 years, 50 cases of lung cancer arose in the group that smoked cigarettes, and 300 cases arose in the group that didn't smoke cigarettes. Calculate the relative risk based on the table and write an interpretation for the relative risk. Show your work on the calculation of relative risk. Lung Cancer No Lung Cancer. Total Smokers 50 450 500 Nonsmokers 300 1,600 1,900 Total. 350 350 350

- Relative Risk = ((50) / (50+450)) / ((300) / (300+1,600)) = 0.1 / 0.16 = 0.63 - Interpretation = People who smoke are 0.63 times as likely to contract lung cancer over 20 years than people who do not smoke. - Reason: The relative risk formula is (A/A+B) / (C/C+D). The criteria for relative risk interpretation is that the exposure is described for both exposed and unexposed groups, the relative risk is provided, the language appropriate to incidence (develop, contract, newly diagnosed) is used to interpret meaning, and the time period of follow up is included.

Please match each level of prevention with its correct, corresponding definition. 1.) Primary Prevention 2.) Secondary Prevention 3.) Mid Prevention 4.) Tertiary Preventiond. a. Prevention during the development/ early stages of the condition b.) Is not a real prevention level c.) Prevention after the condition has occurred d.) Prevention before a condition occurs

1 matches with d. 2 matches with a. 3 matches with b. 4 matches with c.

Odds ratio is used for which studies? a) Case control b) Cohort c) Randomized control trials d) Interventional

A.) Relative risk is used for cohort and RCT studies. Interventional is not the correct answer because RCTs are a form of interventional studies.

What is the purpose of randomization in a clinical trial? A.) Randomization ensures that participants receive a placebo rather than an active treatment. B.) Randomization distributes the known and unknown factors equally in treatment groups in order to minimize bias and confounding. C.) Randomization increases the cost-effectiveness of a study. D.) Randomization guarantees that the treatment group is always larger than the control group.

B.) Randomization in a clinical trial helps in distributing both the known and unknown factors equally in treatment groups. It is important to minimize confounding and bias. It helps researchers find a more accurate comparison between treatment and control groups.

An odds ratio of less than 1 implies that those exposed are... a.) More likely to have the disease b.) Less likely to have the disease c.) No relationship d.) Not enough information known

B.) The answer is B because the odds of the disease occurring in those who are exposed are less than in those not exposed

What is an exposure a.) negative association between the exposure and outcome b.) describes the shift in patterns of morbidity and mortality causes. c.) molecular or genetic markers to trace the development of a disease in a population and to understand transmission, as well as the population structure and evolution of pathogens d.) factor associate with an outcome of interest (behaviors, policies, environment, demographic)

D.)

Calculate the Relative Risk for the table of Disease No Disease Totals Exposed 174 236 410 Not Exposed 89 113 202 Totals 263 349 612

RR = A/ (A+B) / C/ (C+D) RR = (.424) / (.441) RR = .961

T/F: Cohort studies are good for measuring incidence

True Why: Cohort studies provide longitudinal data and also establish that individuals are free from disease (aka at risk) when the study starts

Food Poisoning No Food Poisoning Exposed to Cafeteria Food: 87 | 42 Not Exposed to Cafeteria Food: 130 | 271 Given that the data in the table above was taken from a case-control study investigating if exposure to cafeteria food is related to the development of food poisoning, write out the complete odds ratio or relative risk interpretation.

- People exposed to cafeteria food are 4.32 times as likely to have food poisoning as people not exposed to cafeteria food. - Since this is a case-control study, the appropriate measurement is odds ratio (as opposed to relative risk). - OR = odds of exposure in those with disease / odds of exposure in those without disease - OR = (AxD) / (BxC) - OR = (87x271) / (42X130) - OR = (23,577) / (5,460) - OR = 4.32 - The odds ratio interpretation is made up of the following recipe: - People exposed to (exposure) are (OR) times as likely to have (the disease) as people not exposed to (exposure).

Calculation: In a study conducted about a particular disease, 10,000 individuals were the sample tested on. The results came out that 400 individuals with the disease tested positive as well as 2850 individuals without the disease who tested positive, while 100 individuals with the disease who tested negative as well as 6650 individuals without the disease tested negative. Calculate the sensitivity and specificity of the test

- Sensitivity = True Positives (TP)/True Positives (TP) + False Negatives (FN) = 400 / (400 + 100 ) * 100 = 400 / 500 * 100 = 80% - Specificity = True Negatives (TN)/True Negatives (TN) + False Positives (FP) = 2850 / (2850 + 6650) * 100 = 2850 / 9500 * 100 = 30%

What is a distinctive characteristic of Randomized Controlled Trials (RCTs)? ( Select all that apply) a.) Participants are randomly assigned to different exposure groups. b.) Use of odds ratio as a primary measure of association. c.) Real-time follow-up of individuals, allowing the calculation of incidence. d.) No one has the outcome at the start, representing the population at risk.

A, C, and D

What is epidemiology? a.) An examination of the prevalence and contributing factors to health and illness in communities b.) explains how patterns of morbidity and death causes have changed.Change from infectious to degenerative, chronic illnesses c.) Compared to the unexposed group, the exposed group has a lower chance of the outcome. The exposed group has a 20% lower chance of developing the outcome than the non-exposed group (RR = 0.8). d.) We are certain that our efforts are helping. The study needs to have a justification.

A.)

Which of the following describes the bias for the following scenario? A research study recruits participants directly from clinics who share the same disease diagnosis. However, these cases do not match the numbers which have been collected in town. They believe those cases are those who did not attend those clinics. a.) Selection Bias b.) Non-response bias c.) Exclusion bias d.) Information Bias

A.) Selection bias is based on the methods used to select the population of interest or how participants are recruited. Therefore, the sample and the target population may differ.

If the prevalence increases in a population what happens to the probability of negative tests being correct (negative predictive value)? A.) Decreases B.) Stays the same C.) Increases D.) Cannot be determined from this statement

A.) The answer is A because in places where a condition is incredibly common(high prevalence), the probability of a positive test being correct increases (positive predictive value increases), and the probability of negative tests being correct decreases (negative predictive value decreases).

How do you identify a selection bias in a case-control study? a.) Identify criteria used to determine the case and controls and see if it is related to the exposure b.) Identify criteria used to determine the case and controls and see if it is related to the outcome c.) Identify criteria used to determine exposed and unexposed and see if it is related to the exposure d.) Identify criteria used to determine exposed and unexposed and see if it is related to the outcome

A.) a case-control study uses case and controls and is related to exposures not outcomes.

Which of the following is the equation for Odds Ratio? a.) (A / C) / (B / D) b.) (A x C) / (B x D) c.) (A / B) / (C / D) d.) (B / C) / (A / D)

A.) you are calculating what the odds of the exposed vs the unexposed were. It is a measure to determine an association between exposure and outcome.

What are the proper steps in a Case-Control Study? a.) Identify cases and appropriate controls, measure previous exposures, and then compare the two groups b.) Identify the controls, measure previous exposures, and compare both groups c.) Identify cases, measure previous exposures, and analyze the one-group d.) Identify cases and controls, and compare the two groups.

A.) There will always be more than one group as there is a case group and a control group, identifying the cases and controls is crucial as that's the main part of the study, and previous exposures need to be measured to find the cause.

A study was carried out to look at the relationship between daily caffeine use during pregnancy and the occurrence of low birth weight. Researchers recruited 100 women who had low birth weight infants and 100 women who had normal birth weight infants. Participants were asked to share specific information regarding their caffeine consumption during their pregnancies. What type of study is this? a) Case-control study b) Cohort study c) Experimental study d)Cross-sectional study

A.) because a case-control study compares individuals with a certain outcome (in this case, low birth weight infants) to a control group of individuals who do not have the disease (women with normal birth weight infants). The researchers next collect information from both groups regarding the exposure of interest (daily caffeine usage during pregnancy) to see if there is a link between the exposure and the outcome.

All of the following are strengths of the cohort study design except: a.) Relatively Inexpensive b.) Evaluates multiple outcomes c.) Efficient for rare exposures d.) Demonstrates a clear temporal relationship between exposure and disease

A.) because cohort study designs are not inexpensive. Researchers have to follow participants over time and conduct follow-ups in order to carry out the study correctly.

Which study design is used for hypothesis generation? a.) cross-sectional b.) ecologic c.) case-control d.) a & b e.) none of the above

A.) because descriptive studies are used for hypothesis generation. A cross-sectional study design is a descriptive type of study design, which, in this question, is the only descriptive study. The rest of the answer choices, ecologic and case-control, are analytical studies, which are study designs for hypothesis testing, making choices B, C, D, and E incorrect.

What would happen to the prevalence in this situation: A new medication makes it possible for patients to live with the disease for a longer period of time. a.) Increase prevalence b.) Decrease prevalence c.) Prevalence would stay the same d.) Decrease incidence

A.) because, if people can live with the disease for longer, the more people there will be walking on this earth with the disease in their bodies.

Which of the following describes an Epidemic? a.) Usually refers to a world-wide spread of the disease b.) An increase in the number of cases over past experience for a given population, time and place c.) The habitual presence of the usual number of people with the disease within a geographic area d.) Spanish flu of 1918-1919 which killed more than 50 million people

B.) An endemic disease becomes an epidemic when the number of people who are infected rises above levels that would be expected. A and D are pandemic which is an epidemic occurring over a very wide area and effect a large number of people C is endemic which is restricted to a particular region or area and is constantly present but at manageable levels

Choose the epidemiological study design that is best suited to investigate rare outcomes. A.) Cohort study B.) Case-control study C.) Cross-sectional study D.) Ecological study

B.) Case-control studies select individuals based on the presence or absence of the outcome of interest. Since they become able to start with the identification of rare outcomes.

Which of the mortality indicators informs us about the percentage of individuals diagnosed with a particular disease who subsequently die from that disease? a.) proportionate mortality b.) case fatality rate c.) cause specific mortality rate d.) none of the above

B.) The reasoning why option B is the correct answer is because the definition of "case fatality rate." is a mortality indicator that specifically addresses the percentage of individuals diagnosed with a particular disease who subsequently die from that disease.

Which of the following is the proper way to write a Relative Risk interpretation? a.) People exposed to cigarette use are 0.75 times as more to be newly diagnosed with cancer as people who are not exposed to cigarette smoking. b.) People exposed to cigarette use are 0.75 times as likely to be newly diagnosed with cancer over 10 years as people who are not exposed to cigarette smoking. c.) People exposed to cigarette use are 0.75 times as likely to be newly diagnosed with cancer as people who are not exposed to cigarette smoking. d.) People exposed to cigarette use are 0.75 times as likely to have cancer as people who are not exposed to cigarette smoking.

B.) the formula is " People exposed to [exposure] are RR times as likely to be newly diagnosed with [the outcome] over [length of follow up] as people who are [unexposed]."

Which of the following is FALSE about bias? a.) Bias is systematic deviation of results or inferences from truth b.) Bias occurs due to investigator prejudice c.) Bias leads to results different from truth d.) Bias is often due to an error in the conception and/or design of a study

B.) Bias is a systematic deviation of results or inferences from truth due to errors in the conception and design of a study, or in the collection, analysis, interpretation of reporting of data, that leads to results different from truth. Bias does NOT occur because of investigator prejudice, but is due to ignorance or unavoidable methodological decisions of the investigator(s).

How does Incidence and Prevalence differ? A.) Prevalence is the number of new cases during a specific period of time B.) Incidence is a measure of risk C.) Prevalence is a measure of risk D.) Incidence is the total number of cases in a population

B.) Prevalence is the total number of cases in a population. Incidence is the number of new cases that occur during specified time period in a population at risk for becoming a case.

Screening is a form of which type of prevention? a.) Primary prevention b.) Secondary prevention c.) Tertiary prevention d.) Screening is not a form of prevention

B.) screening is a type of secondary prevention as it is a presumptive identification of disease that takes place during the early stages of the development of disease in order to try and limit its progression.

What would happen to the positive predictive value of a screening test if the prevalence of the disease it was screening for were to decrease in a population. A. PPV would increase B. PPV would decrease C. Sensitivity would decrease D. Specificity would decrease E. NPV would decrease

B.) As less people have a disease, less people screen positive, and the positive test result is less likely to be correct. Sensitivity and specificity never change, and NPV would increase (not decrease) with a lower prevalence of the disease in a population.

Which measure of association is suitable for a Cohort study? A. Incidence B. Relative Risk C. Prevalence D. Odds Ratio E. Both A & C

B.) Relative Risk is the measure of association suitable for a Cohort study because the attributes involved are: good for rare exposures, begins with an exposure assessment, and can be used to calculate incidence.

What level of prevention does screening fall under? a.) Tertiary Prevention b.) Secondary Prevention c.) Primary Prevention d.) Primordial Prevention

B.) Screening is secondary prevention because screening takes place during the early stages of pathogenesis and includes activities that limit the progression of the disease. Primary prevention is the prevention of disease before it occurs, for example, getting your flu shot. Tertiary treatment is receiving treatment to regain optimal health.

Which of the following would NOT be an example of tertiary prevention? a.) Going to physical therapy to help with chronic back pain b.) Waking up everyday at 6am to go on a long run c.) Going to a diabetes management program to help with diabetes control after being diagnosed d.) Going to speech therapy after having a stroke

B.) Tertiary prevention is directed towards later stages of pathogenesis and includes programs for restoring the patientʼs optimal functioning. Therefore, waking up at 6 am to go on a long run would be a primary prevention because it is a healthy lifestyle choice to prevent further health related issues

Descriptive epidemiology classifies the occurrence of disease according to the variables of... A) Incidence, prevalence, and odds ratio. B) Person, place, and time. C) Exposure, outcome, and confounding. D) Sensitivity, specificity, and positive predictive value.

B.) The three main elements of descriptive epidemiology are person, place, and time. Descriptive epidemiology studies aid in generating hypotheses that can be explored by analytic epidemiologic studies.

Which of the following is an example of information bias? a) Participants in a study that volunteer to take part in a study for any reason b) Researchers in a study knowingly (or unknowingly) influence the outcome measurements c) Participants who are participating in the study who choose to respond are significantly different than the participants in the study who choose not to respond d) Population of individuals are put in a situation where they can no longer participate, either by harming them or making them too ill

B.) because A, C, and D are all examples of selection bias, which occurs when one group of participants are systematically favored over the other group. B is an example of information bias because it is an error made on part of data collection.

Gypsy Rose Blanchard is a victim of her mother, Dee Dee Blanchard, who it turned out had made Gypsy a lifelong victim of her Munchausen syndrome by proxy. In the case of Gypsy Rose Blanchard, the best study design would be: A) Ecologic Studies B) Case Report C) Case Series D) Cohort Study

B.) because a case report is focused on one person. This is a hypothesis-generating study focusing on a new symptom and exposure that has not been heavily researched before so that researchers can study the psychological and social effects of Munchausen syndrome by proxy.

Which of the following is NOT a reason we take people out of the denominator when determining incidence? a.) They moved away b.) They were diagnosed before the time period c.) They are above the age of 65 d.) They died

C.) All the other answers are correct therefore it must be C since people above the age of 65 are still relevant in finding incidence. Age does not play a factor in equation.

Which of the following is considered a descriptive study design? A.) Ecologic Studies B.) Cohort Studies C.) Cross Sectional Studies D.) Case Control Studies

C.) Descriptive study are hypothesis generating and distribution of disease focused. The other options are all analytic studies, they are hypothesis testing and determinants of disease focused.

Strengths of cohort studies include all of the following EXCEPT: A.) Collected in "real time" B.) Efficient for rare exposures C.) Not expensive or time consuming D.) Can evaluate multiple outcomes for a given exposure E.) Clear temporal relationship between exposure and disease

C.) The answer is C because options A,B,D,E are all examples of strengths of cohort studies, but C is not a strength because cohort studies are expensive and time consuming. Cohort studies being expensive and time consuming is a weakness.

The Hills Causality Criteria includes all of the following except A) Consistency B) Temporality C) Bias D) Plausibility

C.) because the Hills Causality Criteria include strength of association, consistency, specificity, temporality, biological gradient, plausibility, coherence, and analogy. Bias is an alternate explanation for associations.

Over 100 million people worldwide died from COVID-19 between 2020-2023, it is an example of a.) Epidemic b.) Endemic c.) Pandemic d.) None of the above

C.) because the disease is affecting people across the world.

Which of these is NOT a component of a Randomized Control Trial? A.) masking B.) random assignment of intervention/ control C.) include people who are very different in the study sample D.) similar measurement of outcomes in intervention/control groups

C.) because the study sample should not vary in a RCT, it should be as alike as possible for the proper study design. This helps to ensure the conclusions will be correct.

What is the correct equation to find the odds ratio? a.) (AB/DC) b.) (EC/BA) c.) (AD/BC) d.) (DB/CA)

C.) because to find odds ratio you have to divide the odds of exposure in those with disease by odds of exposure in those without disease. To get these you would divide AxD by BxC.

All of the following are true regarding study designs EXCEPT: A.) Cross sectional designs are considered "hypothesis generating," while cohort studies are considered "hypothesis testing." B.) Case control studies are efficient for rare outcomes/ diseases C.) Cohort studies are efficient for rare exposures D.) Results of Ecologic studies should be used at the individual level

D.) D is not true because ecologic studies are used at the group level, rather than the individual level. The ecologic fallacy occurs when someone erroneously infers information about individuals based only on group data. All the other answers are true regarding study designs.

When calculating incidence, when do you take people out the denominator? A.) They were diagnosed before the period we are looking at B.) They moved from the area before the time period we are looking at C.) They passed away before the period we are looking at D.) All the above

D.) Incidence is the number of new cases that happen during a specific time period in a population at risk for becoming a case. So all those things couldn't be a part of the numerator.

Researchers at the University of Delaware are interested in the relationship between students being Taylor Swift fans and getting on the dean's list. They assembled a group of 600 students, including 346 who reported being a Taylor Swift fan. Over the course of a semester, the researchers followed up and found that 274 of the students who were Taylor Swift fans got on the dean's list. Of the non swifty students, 105 got on the dean's list. Question 1: What kind of study did the researchers use? a.) RCT b.) Case control c.) Double blind study d.) Cohort study

D.) This is a cohort study because the researchers followed the group of students over time.

Which of the following is the equation for Relative Risk? a.) (A/A-B) / (C/C-D) b.) (C/C+D) / (A/A+B) c.) (A/A+D) / (C/C+B) d.) (A/A+B) / (C/C+D)

D.) because you have to separate the exposed from the unexposed to calculate what their risk of a specific outcome may be.

What type of study design involves populations or groups of people as the unit of analysis? A. Cross Sectional B. Surveillance C. Case Control D. Ecologic E. Both A & C

D.) In order for a study design to be deemed ecologic, it needs to focus on a group rather than remaining on the individual level. Ecological fallacy would come into play when the characteristics of a group are attributed to an individual.

Which study designs use relative risk to determine the measure of association? a.) Case-Control b.) Cohort Studies c.) Random Controlled Trials d.) B and C e.) A and C

D.) B and C because Cohort and RCTs use relative risk as case control uses odds ratio

Which of the following can be used to calculate incidence? a.) Case-control studies b.) Cohort studies c.) Randomized controlled trials d.) Both B and C e.) None of the above

D.) Case-control studies can't be used to calculate incidence because we are beginning the study with people who already did or did not develop the disease. Cohort studies and RCTs can be used to calculate incidence because we are beginning with exposed and unexposed participants.

Dr. Lessard and Shazia would like to conduct an experiment without bias. Unfortunately, some bias appeared in the study. Being professionals at their favorite subject, they narrowed the bias down to information bias, leaving it down to random misclassification and non-random misclassification. In the experiment, Dr.Lessard and Shazia both gathered people into the study and separated them into two groups. Dr. Lessard had one group where she measured the height of each patient in the study. Shazia had another group where she had asked patients to record what the patients thought their height was. Identify which misclassification each Dr.Lessard and Shazia had done. a.) Dr.Lessard performed random misclassification and Shazia performed non-random misclassification b.) Dr.Lessard and Shazia both did random misclassification. c.) Dr.Lessard and Shazia are perfect and never mess up. There is no bias whatsoever. d.) Dr. Le

D.) Dr. Lessard performed non-random misclassification by measuring the patient's height, which gave her the exact height of the patient, because Dr.Lessard measured, this is non-random. Shazia performed random misclassification by asking the patients to record their heights. Asking patients to record their heights may have some error because it is not exact and is estimated which makes a poor measurement tool, resulting in random misclassification.

What is a key characteristic of a cohort study design in epidemiology? a.) It begins with the identification of individuals with a specific outcome and looks backward to examine their exposure. b.) It involves randomly assigning participants to different groups to assess the impact of an intervention. c.) It is most suitable for studying rare diseases in a population. d.) It follows a group of individuals over time, recording their exposure status, and assesses the development of outcomes.

D.) because in a cohort study, researchers follow a group of individuals over time, recording their exposure status at the outset, and then assess the development of outcomes. This design is particularly useful for investigating the association between exposures and subsequent outcomes, helping establish temporal relationships and providing insights into causality.

What type of study is not an analytic study design? a.) Case-control b.) Cohort c.) Randomized control trials d.) Ecological e.) Cross - sectional

E.) All of the other study designs are analytic study designs, whereas cross-sectional studies are descriptive.

Which study designs are written by a clinician and include a small number of people? a.) Ecological b.) Cross-sectional c.) Case reports d.) Case series e.) C+D

E.) Because only case reports and case series are written by a clinician. Ecological and cross- sectional studies are not written by a clinician and are usually larger numbers of people than case reports and case series.

When does selection bias occur? A. When selection of participants in the study is not related to the exposure/outcome of interest B. When people are lost for reasons related to the exposure and/or outcome C. When researchers use poor measurement tools to assess outcomes D. It occurs only in cohort studies E. When selection of participants in the study is related to the exposure/outcome of interest

E.) Selection bias occurs when selection of participants in a study is related to the exposure/outcome of interest. In cohort studies it would occur when selection is related to potential for outcome status and for case control studies it would occur when selection is related to exposure status (it does not only occur in cohort studies and randomized control trials/randomization are the only way to eliminate selection bias). Option B is related to loss to follow up and option C is random misclassification.

In a case-control study investigating the association between phone use and brain tumors, participants with a history of brain tumors are more likely to recall their past mobile phone usage compared to those without brain tumors. This discrepancy in being able to recall such information between the two groups could lead to: a) Sampling bias b) Observer bias c) Selection bias d) Confounding bias e) Recall bias

E.) It is actually an example of recall bias, it's not connected to selection, but rather to measurement

T/F: Case control studies can be used to calculate both incidence and prevalence.

False Why: Case control studies cannot calculate incidence, as they are outcome based. The research participants are picked based on whether or not they are sick--this means you cannot calculate "new cases" as the sick individuals are identified only once

T/F: The unit of observation of an ecologic study is an individual.

False Why: Ecologic Studies only study groups as the unit of observation, and the ecologic fallacy states that the information gathered from this type of study cannot always be extrapolated to the individual level.

T/F: In order for a variable to be confounding it has to be in the causal chain

False Why: For a variable to be confounding it cannot be in the causal chain. This is because the causal chain is the biological mechanism that explains the relationship between exposure and the outcome. This also means the way the exposure leads to the outcome.

T/F: In a case-control study you can calculate a relative risk or an odds ratio.

False Why: In a case-control study you can only calculate an odds ratio.

T/F: In cross-sectional studies, exposures and outcomes are measured at different times.

False Why: In cross-sectional studies, exposures and outcomes are measured at the same time in order to assess the prevalence of a disease or of other variables.

T/F: Random misclassification occurs when there are errors that are related to the outcomes or the exposures.

False Why: Random misclassification actually occurs when the error is unrelated to the exposure or outcome status. Non random misclassification is the term used for errors that are related to the outcomes or exposures.

T/F: Selective screening is done with low risk groups

False Why: Selective screening is done with high risk groups

T/F: In a case control study you begin by identifying controls.

False Why: The first step in a case study is to identify the cases, then the controls second. The control group is used to compare the cases to.

T/F: When writing an odds ratio interpretation, the duration of the study must be included.

False Why: The format for an odds ratio interpretation is 'people exposed to (exposure) are (OR) times as likely to have (the disease) as people not exposed to (exposure). When explaining relative risk, the duration must be included.

T/F: In a single blind study , the participants and the investigators are unaware of whether they are participating in the treatment or control conditions

False Why: This answer is false because only the participants are unaware. In a double blind study, both groups are unaware.

T/f: If two variables are correlated with each other, that means that one variable causes the other.

False Why: This is not necessarily true because correlation does not equal causation. There may be indirect, unassociated reasons why the two variables are correlated with each other so we cannot assume one directly causes the other.

T/F: Specificity measures how good the screening test is at identifying sick people.

False Why: This is the definition of sensitivity. Specificity measures how good the screening test is at identifying NOT sick people.

T/F: Vaccinations are an example of secondary prevention

False Why: This statement is incorrect because vaccinations are an example of primary prevention. Vaccinations are considered a primary prevention because they are a prevention of a disease before it occurs.

T/F: Case control studies can be used to calculate incidence

False Why: You are unable to calculate incidence in case control studies because the cases have already taken place and you are only using them to assess an exposure.

T/F: A Cross-Sectional study is a type of hypothesis generating study.

True Why: A cross-sectional study is a type of descriptive study and can be classified as hypothesis generating. Analytic studies are classified as hypothesis testing and include ecologic studies, case-control studies, cohort studies, and randomized control trials.

T/F: Random Misclassification occurs when the error is unrelated to exposure or outcome status

True Why: Random misclassification does occur when there is an error unrelated to exposure or outcome status base off of what we learned in class, this could vary from a poor measurement tool being used to assess outcomes in a cohort study or in a case control study half of the cases and controls were randomly selected they all would be classified as random.

T/F: A cohort study is an analytic design that can calculate relative risk and incidence.

True Why: The two that would be mixed up would be case control and cohort study. Case control can not calculate incidence and the measure of association is odds ratios but a cohort study allows people to calculate incidence and relative risk

A group wants to look at the relationship between diet and diabetes. They looked at 100 people with local people with diabetes and then found another 100 people of a similar demographic without diabetes. They surveyed everyone's eating habits and found that 70 of the participants with diabetes had a high sugar diet. On the other hand, 15 of the participants without diabetes had a high sugar diet. Decide whether you would use Odds Ratio or Relative Risk to analyze this study data and calculate the value. a.) OR: 13.2 b.) RR: 13.2 c.) OR: 3.2 d.) RR: 3.2

a.) This is a case control study because people with the disease(outcome) are identified first and then surveyed to compare exposures to those of a similar demographic but without the identified outcome. Case Control Study=Odds Ratio OR = (A*D)/(B*C) OR = (70*85)/(15*30)=13.2

Researchers study the relationship between maintaining muscle mass in populations over 60 years old and consumption of protein supplements. 100 elderly individuals who have no protein supplementation added to their diet are compared to 100 elderly individuals who add 25-30g of whey protein supplements. Over four years, fat-free mass gained is assessed and interpreted. a.) Odds ratio b.) Relative Risk c.) incidence d.) population at risk

b) because the student must first understand that this is a cohort study. Once the student can identify that this is a cohort study, it should be inferred that relative risk is the measure of association for this kind of study design. Odds ratio, population at risk, and incidence rates are not appropriate for this study design.

Which of the following IS NOT a time variable for descriptive epidemiology? a.) Point Epidemic b.) Group Epidemic c.) Clustering d.) Seasonal Trend

b.) Time variables for descriptive epidemiology include Secular trend, Seasonal trend, Point Epidemic, Clustering; Group epidemic is a made up term.

Which of the following statements describes case reports? a.) case reports are a collection of reports with commonalities b.) case reports are accounts of a single occurrence or small collection of health-related incidents c.) case reports are an examination of exposure and diseases concurrently d.) none of the above

b.) because a case report explains symptoms and potential diagnoses of a noteworthy incident that may be a novel occurrence of an individual patient. The statement that best describes a case report is answer choice B. The first answer choice explains what a case series is, and the third answer choice explains what a cross-sectional study is, making A and C incorrect. Because answer choice B is correct, answer choice D is incorrect.

What is the only study type that eliminates all confounding? a.) Cohort Study b.) Randomized Control Trial c.) Case Control Study d.) Cross Sectional

b.) because the purpose of randomized control trials is to eliminate confounding. When we randomize exposures, other variables are also randomly distributed throughout the population within the study. Therefore, any other variable other than the one being studied can't distort the association between exposure and outcome.

When setting up your 2x2 table for a screening test, what is A? a.) False negative b.) False positive c.) True positive d.) True negative

c.) Because in the table A= true positive, B= false positive, C= false negative, D= true negative. That is the correct way to set up the table.

After being injured in a car accident, a man has surgery to repair his injuries. After the surgery he is prescribed a physical therapy regime to help him regain mobility. What type of prevention is physical therapy an example of? a.) Primary b.) Secondary c.) Tertiary d.) Quaternary

c.) Physical therapy is considered tertiary prevention because it occurs after the main disease/injury and it is used to help minimize or prevent further/lasting damage.

Which of the following is not how we identify a cofounder? a.) Association with exposure b.) Independently associated with the outcome c.) In the causal chain d.) Can be a repeated offender (age, sex, smoking)

c.) because a cofounder can NOT be in the casual chain because it cannot be the way the exposure "causes" the outcome

Which study design, where subjects are randomly assigned to exposures, should be used to measure the efficacy of a new drug to treat COVID-19? a.) Ecologic study b.) Cross-sectional study c.) Case-control study d.) Randomized control trial

d.) because randomized control trials involve the random assignment of subjects into control and intervention groups in order to evaluate the effectiveness of the supposed intervention.

Dean's List - Not on the Dean's List - Totals Swifty: 274 72 346 Non Swifty: 105 149 254 Totals: 379 221 600 What is the incidence of getting on the Dean's list per 100 students? What is the relative risk for swiftys getting on the dean's list?

incidence = 63 p34 100 students RR = 1.9