Epidemiology Midterm
Cohort study
Compares a group of individuals free of disease against a variety of exposures that are hypothesized to increase or decrease the chance of getting the outcome
Case Control study
Compares a group of individuals who have the disease of interest with a group who does not have the disease
Key elements in descriptive epidemiology related to "place"
Country or origin, urban or rural communities, climate (latitude/longitude), geology, weather
A measure of association used to identify the frequency of exposure and the frequency of outcome in cases and quantify that relationship against control data. A. Relative Risk is equal to 1 (RR = 1) or Odds Ratio is equal to 1 (OR = 1) B. Odds Ratio is greater than 1 (OR > 1) C. Relative Risk is greater than 1 (RR > 1) D. Odds Ratio E. Confidence Interval F. Odds Ratio is less than 1 (OR < 1) G. Relative Risk H. Relative Risk is less than 1 (RR < 1)
D. Odds Ratio
Occurs when individuals emphasize the importance of an exposure they believe to be important A. Recall Bias B. Misclassification C. Publicity Bias D. Reporting Bias E. Interviewer Bias F. Non-Response Bias G. Berkson's (Hospital Admission Rate) Bias H. Exclusion Bias
D. Reporting Bias
Broncoville has a population of 100,000. In 2011, there 1,000 deaths in the population from all causes. There were 300 cases of tuberculosis (TB) identified. In 2011, 110 people died of TB. What is the case fatality rate per 1,000 population? Be careful to round only at the very end of mathematical operations; round to two decimal places. A. 1.1 TB deaths per 1,000 population in 2011 B. 0.0011 TB deaths per 1,000 population in 2011 C. 3.667 TB deaths per 1,000 population in 2011 D. 366.67 TB deaths per 1,000 population in 2011
D. 366.67 TB deaths per 1,000 population in 2011
Bladder Cancer Rates in Cigarette Smokers and Nonsmokers Bladder Cancer Rates per 100,000 Men in Grand Junction, Colorado Cigarette smokers 58.0 Nonsmokers 6.4 What is the rate of bladder cancer for male cigarette smokers compared to male nonsmokers? A. 58.0 x 6.4 = 371.2 B. 58.0 - 6.4 = 51.6 C. (58.0 - 6.4) / 58.0 = 88.97 D. 58 / 6.4 = 9.06
D. 58 / 6.4 = 9.06
Non-fatal heart attack Yes No Total HTN Yes 117 13305 13422 HTN No 125 106416 106541 Total 242 119721 119963 What is the rate difference between those with the exposure of interest (Yes) versus those without the exposure of interest (No)? Be careful to round only at the very end of mathematical operations. Round to two decimal places. A. 117 cases of non-fatal heart attack per 100,000 population B. 988 cases per 100,000 C. 871 cases of non-fatal heart attack per 100,000 population D. 754 cases of non-fatal heart attack per 100,000 population
D. 754 cases of non-fatal heart attack per 100,000 population
You are conducting a case-control study about multiple sclerosis (MS) which is more common in Broncoville, a city in the Pacific Northwest of the US, than in other areas. What would be an appropriate control group? A. People born and raised in the Pacific Northwest B. People who are of equal age, gender, and socio- economic status C. A nationwide sampling of only people without multiple sclerosis (MS) D. A and B E. All of these
D. A and B
When a new treatment is developed that prevents death but does not produce recovery from a disease, the following will occur: A. Incidence of the disease will increase. B. Incidence and prevalence of the disease will increase. C. Prevalence of the disease will decrease. D. Prevalence of the disease will increase
D. Prevalence of the disease will increase.
Investigators are studying an outbreak of TB in a Russian prison whose population is 1500. They found that 146 prisoners on Cell Block A were diagnosed with TB. On Cell Block B, seven prisoners were diagnosed with TB. The two Cell Blocks are completely isolated from each other and each contain 750 prisoners. Develop a 2 x 2 table calculating the Odds Ratio (OR) for Cell Block A. Interpret the OR. Be careful to round only at the very end of mathematical operations. Round to two decimal places. A. Prisoners on Cell Block A are 25.66 times less likely to be diagnosed with TB. Being assigned to Cell Block A is good for prisoners' health. B. Prisoners on Cell Block A are 99.96 times more likely to be diagnosed with TB. Being assigned to Cell Block A is dangerous to prisoners' health. C. Prisoners on Cell Block A are 20.86 times less likely to be diagnosed with TB. Being assigned to Cell Block A is good for prisoners' health. D. Prisoners on Cell Block A are 25.66 times more likely to be diagnosed with TB. Being assigned to Cell Block A is dangerous to prisoners' health. E. Prisoners on Cell Block A are 20.86 times more likely to be diagnosed with TB. Being assigned to Cell Block A is dangerous to prisoners' health.
D. Prisoners on Cell Block A are 25.66 times more likely to be diagnosed with TB. Being assigned to Cell Block A is dangerous to prisoners' health.
Follows a group of subjects over time, first collecting baseline health data and exposure information, then investigates, usually over years, as the outcomes manifest. A. Experimental B. Retrospective Cohort C. Correlational D. Prospective Cohort E. Cohort F. Ecologic G. Case-Control H. Cross-Sectional
D. Prospective Cohort
Choose the best answer for the following: Number of women in Woodbury who died from lung cancer last year divided by Number of women in Woodbury who died from breast cancer last year A. Mortality rate B. Incidence proportion C. Proportion D. Ratio
D. Ratio
Random error, or sampling variability can be reduced by A. an increase in sample size B. a change in study design C. improving instrumentation D. all of the above
D. all of the above
If you take the MCAT exam four times and you receive the same score all four times, we may conclude that the test is _____, but not necessarily_______. A. valid, important B. valid, reliable C. reliable, accurate D. reliable, valid
D. reliable, valid
What are the two assumptions which guide epidemiology? A. Disease does not occur at random. B. Only the good die young C. Disease is unpredictable. D. Disease has causal and preventative factors that can be identified through systematic study of populations.
Disease does not occur at random. Disease has causal and preventative factors that can be identified through systematic study of populations.
A. Relative Risk is equal to 1 (RR = 1) or Odds Ratio is equal to 1 (OR = 1) B. Odds Ratio is greater than 1 (OR > 1) C. Relative Risk is greater than 1 (RR > 1) D. Odds Ratio E. Confidence Interval F. Odds Ratio is less than 1 (OR < 1) G. Relative Risk H. Relative Risk is less than 1 (RR < 1)
E. Confidence Interval
A. Recall Bias B. Misclassification C. Publicity Bias D. Reporting Bias E. Interviewer Bias F. Non-Response Bias G. Berkson's (Hospital Admission Rate) Bias H. Exclusion Bias
E. Interviewer Bias
Communities P and Q have equal age-adjusted mortality rates. Community P has a lower crude mortality rate than Q. One may conclude that: A. The two communities have identical age distributions B. Diagnosis is more accurate in P than Q C. P has an older population than Q D. Diagnosis is less accurate in Q than P E. P has a younger population than Q
E. P has a younger population than Q
Incidence is defined as: A. The number of disease cases in a population at a given time. It is calculated by dividing the disease cases at a specified time by the number of persons at risk for having the disease at that specified time. B. The number of new cases in a population. It is calculated by dividing the number of disease cases by the number of persons at risk for having the disease. C. The number of new cases in a population at a given time. It is calculated by dividing the number of disease cases at a specified time by the number of persons at risk for having the diseases at that specified time. D. The number of disease cases in a population at a given time. It is calculated by dividing the number of new disease cases at a specified time by the number of persons at risk for having the disease at that specified time. E. The number of new cases in a population at a given time. It is calculated by dividing the number of new disease cases at a specified time by the number of persons at risk for having the disease at that specified time.
E. The number of new cases in a population at a given time. It is calculated by dividing the number of new disease cases at a specified time by the number of persons at risk for having the disease at that specified time.
The "normal" or expected amount of disease occurrence.
Endemic
Higher than the expected number of cases.
Epidemic
A histogram of the distribution of cases of a disease or condition by time of onset
Epidemic Curve
What do you call the visual representation of the number of cases that have occurred (on one axis) by the time of occurrences (on the other axis)? a. A line list b. Epidemiologic curve c. Case definition d. Pie chart
Epidemiologic curve
When setting up a 2 x 2 table for a cohort study, how do you label your table to the left of cell A? blank blank blank Total blank A B A+B blank C D C+D Total A+C B+D A+B+C+D Outcome of interest (what you are solving for) Exposure of interest (what you are solving for) The number unexposed who developed the outcome (what you are solving for) It doesn't matter how you label your table, the math will come out right if you apply the correct formula.
Exposure of interest (what you are solving for)
There is less incidence of disease (outcome) in cases than in controls. Indicates the exposure under study is a possible protective factor in mitigating the disease (outcome). When expressed mathematically, is always converted to a percentage. A. Relative Risk is equal to 1 (RR = 1) or Odds Ratio is equal to 1 (OR = 1) B. Odds Ratio is greater than 1 (OR > 1) C. Relative Risk is greater than 1 (RR > 1) D. Odds Ratio E. Confidence Interval F. Odds Ratio is less than 1 (OR < 1) G. Relative Risk H. Relative Risk is less than 1 (RR < 1)
F. Odds Ratio is less than 1 (OR < 1)
Occurs when individuals who fail to repond to a call to participate in a study are different from those who do respond A. Recall Bias B. Misclassification C. Publicity Bias D. Reporting Bias E. Interviewer Bias F. Non-Response Bias G. Berkson's (Hospital Admission Rate) Bias H. Exclusion Bias
F. Non-Response Bias
Used to assess the association between exposure and disease rates among different populations during the same time period. A. Experimental B. Retrospective Cohort C. Correlational D. Prospective Cohort E. Cohort F. Ecologic G. Case-Control H. Cross-Sectional
F. Ecologic
Generally, confidence interval decreases as sample size decreases. True or False?
False
Passive surveillance yields data in response to aggressive outreach from local and/or state public health agencies. True or False?
False
You conduct a study to examine the association between an exposure and an outcome. You calculate a relative risk <1.0. This means that those with the exposure were more likely to develop disease than those without the exposure. True or False?
False
A. Recall Bias B. Misclassification C. Publicity Bias D. Reporting Bias E. Interviewer Bias F. Non-Response Bias G. Berkson's (Hospital Admission Rate) Bias H. Exclusion Bias
G. Berkson's (Hospital Admission Rate) Bias
A. Relative Risk is equal to 1 (RR = 1) or Odds Ratio is equal to 1 (OR = 1) B. Odds Ratio is greater than 1 (OR > 1) C. Relative Risk is greater than 1 (RR > 1) D. Odds Ratio E. Confidence Interval F. Odds Ratio is less than 1 (OR < 1) G. Relative Risk H. Relative Risk is less than 1 (RR < 1)
G. Relative Risk
Compares (matches) two groups to identify probable causes of a rare disease A. Experimental B. Retrospective Cohort C. Correlational D. Prospective Cohort E. Cohort F. Ecologic G. Case-Control H. Cross-Sectional
G. Case-Control
Cross-Sectional
Good for estimating the prevalence of an exposure or disease in a population at one specific point in time.
Correlational (LSQ MOD E)
Good for formulating, but not testing, a hypothesis; seeks to find relationships between variables such as age, time, or exposure and looks for frequency of disease at the population level at the same period of time or in differinterm-136g periods of time.
Case-Control study design (LSQ MOD E)
Good for identifying the effects of a rare diseases and is always retrospective; this type of study matches controls to cases to provide information on the exposure distribution so rates of disease in exposed and unexposed groups can be compared.
Cohort study design
Good for identifying the effects of a rare exposure; this type of study compares the occurrence of an outcome in exposed versus unexposed groups, in order to understand the level of risk associated with acquiring a disease between the two groups
Strengths of case control studies include: Good for rare exposures, multiple outcomes, and allow a direct measurement of the incidence of disease in exposed and unexposed groups Good for rare diseases with long latent periods, outbreak investigations, and are relatively inexpensive Good for measuring health status, provide good data on the prevalence of exposure and disease, and are a good way to formulate hypothesis Designed for proving an association between an exposure and an outcome Good for Investigating whether hypothetical relationships actually exist, require a short duration or study period, and are relatively inexpensive
Good for rare diseases with long latent periods, outbreak investigations, and are relatively inexpensive
Strengths of cohort studies include: Good for rare diseases with long latent periods, outbreak investigations, and are relatively inexpensive Designed for proving an association between an exposure and an outcome Useful for measuring health status, provide good data on the prevalence of exposure and disease, and are a good way to formulate hypothesis Good for investigating whether hypothetical relationships actually exist, require a relatively short duration or study period, and are relatively inexpensive Good for rare exposures, multiple outcomes, and allow a direct measurement of the incidence of disease in exposed and unexposed groups
Good for rare exposures, multiple outcomes, and allow a direct measurement of the incidence of disease in exposed and unexposed groups
A. Recall Bias B. Misclassification C. Publicity Bias D. Reporting Bias E. Interviewer Bias F. Non-Response Bias G. Berkson's (Hospital Admission Rate) Bias H. Exclusion Bias
H. Exclusion Bias
A. Relative Risk is equal to 1 (RR = 1) or Odds Ratio is equal to 1 (OR = 1) B. Odds Ratio is greater than 1 (OR > 1) C. Relative Risk is greater than 1 (RR > 1) D. Odds Ratio E. Confidence Interval F. Odds Ratio is less than 1 (OR < 1) G. Relative Risk H. Relative Risk is less than 1 (RR < 1)
H. Relative Risk is less than 1 (RR < 1)
Good for estimating the prevalence of an exposure or disease in a population at one specific point in time. A. Experimental B. Retrospective Cohort C. Correlational D. Prospective Cohort E. Cohort F. Ecologic G. Case-Control H. Cross-Sectional
H. Cross-Sectional
Experimental
In an attempt to study the effect of vitamin C supplementation on the prevention of the common cold, researchers randomly assigned volunteers to take a prescribed amount of vitamin C or to take a placebo, and then followed up to see if the exposed group developed fewer colds than the unexposed group.
A measure of disease frequency that indicates the force of morbidity or the probability that a disease will develop in a given period of time. Calculated by dividing the number of new cases by the total number of susceptible people at the beginning of the study period
Incidence Rate
Misclassification
Interviewers ask study participants to indicate their nationality. An interviewer forgets to ask this question and places an Asian participant in the Chinese category, when that participant is really Japanese.
Retrospective Cohort
Investigates rare exposures in a group of subjects to determine probable causes of a disease with a long latent period. Researchers use health and other official records to retrieve data from prior years or decades.
Who is the "father" of Epidemiology? A. Louis Pasteur B. William Farr C. John Snow D. Robert Koch
John Snow
Cohort studies are most appropriate for Rare diseases Looking at multiple effects of a single exposure Common exposures Both b and c are correct
Looking at multiple effects of a single exposure
Which discipline is NOT part of the "Epi Onion"? A. Medicine B. Microbiology C. Mortician D. Sociology
Mortician
Incidence
New onset cases in the population at risk over a set time
Incidence
New onset cases in the population at risk over a set time.
No partial credit will be awarded. Select all that apply: In order to be a confounder, the variable must Not be an intermediate variable in the causal pathway between exposure and disease Modify the exposure's effect on the disease Be associated with the exposure under study Be a risk factor for the disease of interest Be an intermediate variable in the causal pathway between exposure and disease
Not be an intermediate variable in the causal pathway between exposure and disease Be associated with the exposure under study Be a risk factor for the disease of interest
The theory that there is no association between the exposure and the outcome.
Null hypothesis
Recall Bias
Occurs when an individual with a disease/outcome is concerned about remembering potential causes
Berkson's Bias
Occurs when hospitalized patients are not representative of the target population
Reporting Bias
Occurs when individuals emphasize the importance of an exposure they believe to be important
Publicity Bias
Occurs when study subjects respond to a call for cases because the topic has been in the media
Selection Bias
Occurs when the relationship between exposure and disease is different for those who participate and those who would be theoretically eligible for study, but who do not participate which results in a distortion of the study findings. Examples include healthy worker effect bias, nonresponse bias, etc.
Internal Validity
Overall study results are close to the truth about the population under study
The three key elements of descriptive epidemiology.
Person, place, and time
Epidemiology studies disease occurrence among A. individuals B. causative agents C. health phenomena D. populations
Populations
On the End of Module Quiz, the Midterm, and the Final, you will be required to enter only numbers into your answer, placing a leading 0 in front of the decimal (ie: 0.89). Round to two decimal places after completing mathematical operations. A retrospective cohort study is conducted to evaluate the relationship between supplemental use of calcium and the risk of hip fractures in 1000 post-menopausal women. Of the 730 women with hip fractures, 180 reported regularly taking calcium. Of the 270 women who did not have a hip fracture during this same time period, 156 reported no calcium supplements. Develop a 2 x 2 table. What is the relative risk of suffering a hip fracture if you regularly took calcium as a supplement? RR = 0.42 RR = 0.45 RR = 0.58 RR = 0.79 RR = 0.21
RR = 0.79
On the End of Module Quiz, the Midterm, and the Final, you will be required to enter only numbers into your answer, placing a leading 0 in front of the decimal (ie: 0.89). Round to two decimal places after completing mathematical operations. An ambi-directional cohort study was conducted to evaluate the relationship between obesity and the risk of heart disease in people who primarily eat out as opposed to eating at home. Investigators selected 800 individuals for study. Of the 400 people who primarily eat out, 167 people were found to be obese and 58 people who primarily eat at home were found to be obese. Develop a 2 x 2 table. What is the relative risk of being obese if you eat out often? RR = 1.82 RR = 2.87 RR = 4.23 RR = 2.88 RR = 1.83
RR = 2.88
Which of these is not a determinant of disease? A. occupational exposure B. aging C. random event D. socio-political factors
Random event
A measure of association or relationship between the incidence in the exposed and that in the unexposed. Calculated by dividing the new onset cases by those not exposed to the factor
Relative Risk
There is a larger incidence of the disease in the exposed than in the unexposed and the exposure to the factor seems to increase the probability of developing the disease. This means the relationship between exposure and outcome is more likely.
Relative Risk is greater than 1 (RR > 1)
There is a smaller incidence in the exposed than in the unexposed and the exposure to the factor seems to decrease the probability of developing the disease. This means the relationship between the exposure and the outcome is less likely.
Relative Risk is less than 1 (RR < 1)
Which of the following is NOT part of understanding the distribution of a disease? A. Where B. When C. Who D. Risk factors
Risk factors
Secondary Prevention
Seeks to diagnose disease early and begin treatment; screening
Primary prevention
Seeks to lower the occurence of disease: health promoting behavior, health education, protective equipment, vaccination
Tertiary Prevention
Seeks to promote rehabilitation, restoring patients to a maximum optimal functional level
In the case study on baldness and CHD, the "crude" or overall 2 x 2 table showed that men who were bald were 4.08 times more likely to develop CHD than men who were hairy. To explore age as a possible confounding variable, what did you do next? Stratified the group into those with new onset CHD versus chronic CHD Stratified the group by age into those who exercise regularly and those who did not to explore further Stratified the group into bald and hairy men to explore further Stratified the group by age into older and younger groups to explore further
Stratified the group by age into older and younger groups to explore further
In the case study on baldness and CHD, ultimately what did you determine? That age was a confounding variable because adjusting for age changed the relative risk That age was a confounding variable because adjusting for age changed the incidence of CHD That age was not a confounding variable because adjusting for age did not change the relative risk That age was not a confounding variable because adjusting for age did not change hair growth
That age was a confounding variable because adjusting for age changed the relative risk
Mean
The average, a value that is computed by dividing the sum of a set of terms by the number of terms
Mode
The most frequent value(s) in the data set
Mode
The most frequent value(s) in the data set.
When setting up a 2 x 2 table for a cohort study, what variable goes in cell A? blank blank blank Total blank A B A+B blank C D C+D Total A+C B+D A+B+C+D The number unexposed who did not develop the outcome The number exposed who did not develop the outcome The number exposed who developed the outcome The number unexposed who developed the outcome
The number exposed who developed the outcome
Median
The value in the center of the data set when ordered from lowest to highest.
Median
The value in the center of the the data set when ordered from lowest to highest
A disease outbreak is called a pandemic when it spreads across several or many countries and affects many people. True or False?
True
All proportions are ratios, but not all ratios are proportions.
True
An ecological fallacy is an error of reasoning (bias) which occurs when an association between variables in a target population is applied to individuals members of that population (or vice versa). True or False?
True
An ecological fallacy is the bias that may occur because an association found at the population level does not necessarily represent the association found at the individual level. True or False?
True
Another name for systematic error is bias. True or False?
True
Another word for "determinants" of disease is "risk factors." True or False?
True
Bias is an error in design or execution of a study that produces results that are consistently distorted in one direction and lead to an incorrect assessment of the association between the factor and the disease under study. True or False?
True
Broncoville University has received a grant to study neighborhoods and communities to assist the City Planning and Zoning Committee with future housing development plans. Homeowners from older neighborhoods and communities with parks, playgrounds, and walking paths are recruited as are homeowners from new subdivisions, mixed housing, and urban-rural transition areas. The homeowners are followed for three years to evaluate the impact of parks, playgrounds, and walking paths on 1. Number of days per week using parks, playgrounds, and walking paths 2. Perception of the ease of accessing physical activity options and 3. Overall satisfaction and engagement in the neighborhood. Other data such as age, type of work, and weight are also collected. The investigator is conducting a prospective cohort study. True or False?
True
Cohort studies may be either retrospective, prospective or ambi-directional. True or False?
True
Descriptive epidemiology describes the general characteristics of the distribution of a disease particularly in relation to person, place and time and include ecologic and correlational studies, case reports, and case studies. True or False?
True
In 2009, six people died of H5N1 avian influenza out of 18 persons infected with H5N1 avian influenza. This means the case fatality rate was 33%. True or False?
True
In epidemiology, a determinant is a factor or event capable of bringing about a change in health. True or False?
True
Observational epidemiology is concerned with the health effects of specific exposures and include cohort, case-control, and cross-sectional studies. True or False?
True
Relative risk may be less than one (decreased risk in the exposed group) or greater than one (increased risk in the exposed group). True or False?
True
The frequency of disease occurence may differ from population to population. True or False?
True
Ecologic study design
Used to assess the association between exposure and disease rates among different populations during the same time period but not necessarily the same (geographic) area.
Enter only numbers into your answer. Place a leading 0 in front of the decimal (ie: 0.89). Round to two decimal places after completing mathematical operations. You work for Bronco-gena, a cosmetics company looking to revise their sunscreen advertising campaign. You are tasked with evaluating the relationship between sun screen use and melanoma (skin cancer). You conduct a case control study of 10,000 subjects and find the following: of the 200 cases of skin cancer, 173 reported not using sun screen and of the 9,800 controls, 9,624 reported not using sun screen. What is the odds ratio of contracting skin cancer if you did not use sun screen?
0.12
To receive full points, you must convert your mathematical answer to a percentage and include it in your interpretation In the previous question you were asked to calculate the odds ratio for developing skin cancer if you did not use sun screen. 1. Using correct interpretation formatting, what does your statistical odds ratio answer mean? 2. What recommendation would you make to the Board at Bronco-gena regarding sun screen use? What would your ad campaign tell people about your product?
0.12 x 100 = 12% 100% - 12% = 88% 1. Cases who developed skin cancer were 88% less likely to NOT use sun screen than controls. 2. Failing to use Bronco-gena sun screen can lead to skin cancer. You should always buy and apply Bronco-gena sun screen to keep you and your family safe from skin cancer. Remember your fomatting: Cases who develop the outcome are x times more/less likely to have the intervention than controls
In a recent retrospective cohort study in Lake Mantioc, Wisconsin, researchers found eight people have disappeared into the lake over the last 35 years and an additional new drowning has occurred under suspicious circumstances. Epidemiologists Ford and Hamill accessed patient records, autopsy reports, and interviewed surviving family members. The results are summarized in the table below: Drowned Did Not Drown Total Expert Swimmers 6 15 21 Unable to Swim 3 76 79 Total 9 91 100 What is the incidence of drowning for expert swimmers? Answers are rounded to two decimal places. If your answer is less than 1, place a 0 before the decimal (ie: 0.62)
0.29
Enter only numbers into your answer. Place a leading 0 in front of the decimal (ie: 0.89). Round to two decimal places after completing mathematical operations. Central Line Associated Bloodstream Infection (CLABSI) is a life threatening, hospital-acquired infection which can lead to patient death and is preventable by universal infection-prevention precautions (hand hygiene, sterile technique, "scrubbing the hub," proper IV tubing changes, and chlorhexadine skin preparation during dressing changes). State health officials and the Legislature have become concerned about this issue and ask you as an infection prevention specialist to make a recommendation. You conduct a retrospective cohort study, examining 22,000 inpatient hospital records from medical-surgical units to evaluate the relationship between nurse-to-patient ratios and CLABSI. You define nurse-to-patient on ratios as "light" (four or less patients per nurse) and "heavy" (five or more patients per nurse). You conduct a cohort study and find the following: 13,908 patients consistently had a nurse with a "heavy" patient load and 8,092 patients consistently had a nurse with a "light" patient load. Of patients assigned to a nurse with a "heavy" patient load, 880 CLABSI infections occurred. Patients assigned to a nurse with a "light patient load had 167 CLABSI infections. Develop a 2 x 2 table. A. Calculate the incidence of CLABSI cases with a nurse with a heavy patient load [1] B. Calculate the incidence of CLABSI cases with a nurse with a light patient load [2] C. What is the relative risk of developing CLABSI if you have a nurse with a heavy patient load? [3]
1. 0.06 2. 0.02 3. 3.07
Enter only numbers into your answer. If the answer is a whole number, enter only the whole number (ie 7). Round to two decimal places after completing mathematical operations. For part B, I will assume you are expressing this as a percent: do NOT place a % sign after your answer. The incidence of myocardial infarction (MI) among nonsmokers in the population is 1 case per 1,000 persons. The incidence of myocardial infarction among smokers in the population is 4 cases per 1,000 persons. Assume 35% of the population smokes. Develop a 2 x 2 table. A. Calculate the RR of MI for smokers [1] B. Calculate the attributable risk (AR) for smoking on MI. [2]
1. 4 2. 51.22
In the previous question you were asked to calculate the odds ratio for cases who watch more than five hours of AMC's The Walking Dead each week. 1. Using correct interpretation formatting, what does your statistical odds ratio mean? 2. What public health message would you disseminate? Please write your answer in the space provided.
1. Cases are who believe the zombie apocalypse could happen are 5.56 times more likely to watch greater than five hours of AMC's The Walking Dead than controls. 2. Watching greater than five hours of the The Walking Dead may increase the risk of believing a zombie apocalypse could happen and you could end up on the Broncoville Behavioral Health Registry. Remember your fomatting: Cases who develop the outcome are x times more/less likely to have the intervention than controls
When setting up a 2 x 2 table for a case-control study, how do you label your table 1. to the left of cell A and 2. above cell A ? blank blank blank Total blank A B A+B blank C D C+D Total A+C B+D A+B+C+D 1. Exposure of interest (what you are solving for) 2. Cases with the outcome of interest 1. The number unexposed who developed the outcome (what you are solving for) 2. Cases 1. Outcome of interest (what you are solving for) 2. Cases with the exposure of interest 1. Exposure of interest (what you are solving for) 2. Outcome of interest 1. Cases with the outcome of interest (what you are solving for) 2. Exposure of interest
1. Exposure of interest (what you are solving for) 2. Cases with the outcome of interest
When setting up a 2 x 2 table for a cohort study, how do you label your table 1. to the left of cell A and 2. above cell A? blank blank blank Total blank A B A+B blank C D C+D Total A+C B+D A+B+C+D 1. Exposure of interest (what you are solving for) 2. Those with the outcome of interest 1. It doesn't matter how you label your table. 2. The math will come out right if you apply the correct formula. 1. The number unexposed (what you are solving for) 2. The number of exposed 1. Exposure of interest (what you are solving for) 2. Cases 1, Outcome of interest (what you are solving for) 2. Those with the exposure of interest
1. Exposure of interest (what you are solving for) 2. Those with the outcome of interest
In the previous question, you were asked to calculate the relative risk of developing CLABSI if you were a patient with a nurse who had a "heavy" patient load. Central Line Associated Bloodstream Infection (CLABSI) is a life threatening, hospital-acquired infection which can lead to patient death and is preventable by universal infection-prevention precautions (hand hygiene, sterile technique, "scrubbing the hub," proper IV tubing changes, and chlorhexadine skin preparation during dressing changes). 1. Using correct interpretation formatting, what does your statistical relative risk mean? 2. As an infection-prevention specialist, what recommendations would you make to state health officials and the Legislature? What changes would you advocate for these regulating agencies regarding the risk of heavy patient loads? What would you think if your loved one was assigned to a nurse with a heavy patient load? Please write your answer in the space provided.
1. Patients with a nurse assigned to them with a "heavy" patient load were 3.07 times more likely to get a CLABSI infection than those who had a nurse with a "light" patient load. 2. "Heavy" nurse to patient ratios increase the likelihood of CLABSI infections. This is a life-threatening preventable infection. Regulations or legislation should be put in place limiting the number of patients assigned to nurses. As a family member, I would demand better care for my loved one. Remember your relative risk formating: People who [exposure] are [numeric value] times [more/less] likely to develop [outcome] than people who did not have the [exposure].
In the previous question you were asked to calculate the relative risk for developing an MI if you smoked. 1. Using correct interpretation formatting, what does your statistical relative risk answer mean? 2. What basic public health message would you disseminate to people who haven't started smoking? 3. What does your numeric attributable risk answer mean? 4. If you could effectively intervene with the 35% of smokers in your town, how would that effect MI deaths?
1. Residents who smoked were four (4) times more likely to have an MI than non-smokers. 2. Smoking can lead to MI so you should not start smoking. 3. 51.22% of MI deaths is attributed to (caused by) smoking. 4. If I can convince the 35% of the population that smokes to stop, MI deaths would decrease by 51.22% Remember your relative risk formating: People who [exposure] are [numeric value] times [more/less] likely to develop [outcome] than people who did not have the [exposure].
Prospective Cohort
200 babies were followed from birth to age five to determine if those whose mothers smoked during pregnancy were more likely to have respiratory infections in the first five years of life than those whose mothers did not smoke during pregnancy. The findings supported the investigators' assumption that smoking during pregnancy increases the frequency of respiratory infections in young children.
Since October 2016, a total of 1,023 persons infected with Salmonella Saintpaul with the same genetic fingerprint have been identified in the following states. These were identified because clinical laboratories in all states send strains from ill persons to their state public health laboratory for characterization. The number of ill persons identified in each state is as follows: Arkansas (10 persons), Arizona (39), California (342), Colorado (8), Connecticut (4), Florida (1), Georgia (18), Idaho (81), Kansas (14), Kentucky (1), Maine (12), Maryland (25), Massachusetts (18), Michigan (4), Minnesota (2), Missouri (12), New Hampshire (3), Nevada (4), New Jersey (4), New Mexico (85), New York (25), North Carolina (5), Ohio (6), Oklahoma (19), Oregon (7), Pennsylvania (6), Tennessee (6), Texas (226), Utah (2), Virginia (22), Vermont (1), Washington (4), Wisconsin (6), and the District of Columbia (1). What percent of cases are from the state with the most cases? A. 33.43% B. 3.43% C. 22.09% D. 44.22% E. 33%
33.43%
Enter only numbers into your answer. Place a leading 0 in front of the decimal (ie: 0.89). Round to two decimal places after completing mathematical operations. A case-control study was conducted in Broncoville to evaluate whether the amount of time spent watching The Walking Dead on AMC influences the risk of believing the zombie apocalypse could happen. Exposure was divided into those watching summer (or midwinter) reruns of AMC's The Walking Dead more than five hours a week or watching The Walking Dead only occasionally if at all. Investigators identified 500 cases from the Broncoville Behavioral Health Registry who believed a zombie apocalypse could happen and matched 1500 controls. The study found 357 cases and 465 controls watched more than five hours of AMC's The Walking Dead per week. Develop a 2 x 2 table. Calculate the odds ratio for cases who watch greater than five hours of AMC's The Walking Dead each week
5.56
In a recent retrospective cohort study in Lake Mantioc, Wisconsin, researchers found eight people have disappeared into the lake over the last 35 years and an additional new drowning has occurred under suspicious circumstances. Agents Ford and Hamill accessed patient records, autopsy reports, and interviewed surviving family members. The results are summarized in the table below: Drowned Did Not Drown Total Expert Swimmers 6 15 21 Unable to Swim 3 76 79 Total 9 91 100 What is the relative risk of drowning in Lake Mantioc if you are an expert swimmer? Answers are rounded to two decimal places. If your answer is less than 1, place a 0 before the decimal (ie: 0.62) Formula: [A / (A + B)] / [C / (C + D)]
7.52
Information bias
A kind of bias which occurs as a result of measurement error in both exposure and disease. Examples include recall bias, interviewer bias, etc.
Confidence Interval
A range of values thought to contain the true value a predetermined proportion of the time.
Nonresponse bias
A study following the health of elderly people and the associated lifestyles in the U.S. finds that they have less people in the 90+ age range returning for follow-up even though they are still alive.
Case Control
A study was undertaken to test the hypotheses that chewing tobacco increases the risk of stomach cancer. Detailed historical data on chewing tobacco use were collected from 400 subjects with stomach cancer and compared to the same historical data from matched subjects. The results revealed that chewing tobacco was not a significant risk facor for stomach cancer.
Recall bias
A survey question asks a patient if they have ever taken flurosemide in their lifetime. The participant thinks he has taken it before, but isn't sure, so marks "yes".
Retrospective Cohort
A total of 825 insulation workers employed between 1941 and 1944 were identified from the personnel records of three large insulation manufacturing plants in the southeastern U.S. in 1975. During the period 1941-1975, 26 deaths from lung cancer were discovered among the workers. Only six lung cancer deaths, however, were reported among a comparable group of 700 coworkers who did not work with insulation during the same time period. The investigators had postulated that exposure to the insulation material increases the risk of lung cancer.
No partial credit will be awarded. Which of the following are determinants of disease? (Select all that are correct) A. Carcinogens or chemicals B. Behaviors/habits/lifestyles C. Socio-political factors D. Time of day
A. Carcinogens or chemicals B. Behaviors/habits/lifestyles C. Socio-political factors
No partial credit will be awarded. Select all that apply. Outbreak Investigations seek to: A. Communicate findings to the public and to public health officials B. Formulate a hypothesis C. Take immediate control measures D. Confirm an endemic disease is present in a population E. Determine attack rates F. Define a case and conduct a case finding
A. Communicate findings to the public and to public health officials B. Formulate a hypothesis C. Take immediate control measures E. Determine attack rates F. Define a case and conduct a case finding
No partial credit will be awarded. Select all that apply. Which of the following represent the aspect of "place" in descriptive epidemiology? A. Latitude, longitude, and climate B. What month it is C. Geography of an area D. None of the above E. How many people live in a household F. All of the above
A. Latitude, longitude, and climate C. Geography of an area
No partial credit will be awarded. Select all the apply to a population at risk in epidemiology: A. People who live in a certain geographic area B. People who cannot get the disease you are interested in studying/preventing C. People who share life styles/life events D. People who have the disease you are interested in studying/preventing E. A group with common characteristics F. People who use the same resources
A. People who live in a certain geographic area C. People who share life styles/life events E. A group with common characteristics F. People who use the same resources
A. Recall Bias B. Misclassification C. Publicity Bias D. Reporting Bias E. Interviewer Bias F. Non-Response Bias G. Berkson's (Hospital Admission Rate) Bias H. Exclusion Bias
A. Recall Bias
Incidence in the exposed and the unexposed is the same and the null hypothesis is true. A. Relative Risk is equal to 1 (RR = 1) or Odds Ratio is equal to 1 (OR = 1) B. Odds Ratio is greater than 1 (OR > 1) C. Relative Risk is greater than 1 (RR > 1) D. Odds Ratio E. Confidence Interval F. Odds Ratio is less than 1 (OR < 1) G. Relative Risk H. Relative Risk is less than 1 (RR < 1)
A. Relative Risk is equal to 1 (RR = 1) or Odds Ratio is equal to 1 (OR = 1)
In a recent study of dental erosion in 5-year-old children, 202 healthy school-attending children were selected for study. The investigators recorded the erosion level on their maxillary deciduous incisors and whether or not their communities used fluoridated water. The results are summarized in the table below: Dental Erosion in 5-Year-Old Children Evidence of Erosion No Evidence of Erosion Total Fluori- 46(a) 30(b) 76 dated Area Non- fluori- 77(c) 37(d) 114 dated Area Total 123 67 190 What is the incidence rate for the non fluoridated area? Be careful to round only at the very end of mathematical operations; round to two decimal places. A. 0.68 new cases of dental erosion in the non-floridated area B. 0.01 new cases C. 0.61 new cases of dental erosion in the floridated area D. 0.89 new cases of dental erosion in the non-floridated area
A. 0.68 new cases of dental erosion in the non-floridated area
Broncoville has a population of 467,443. In 2014, there 958 deaths in the population from all causes. There were 153 cases of community acquired pneumonia (PNA) identified. In 2014, 38 people died of PNA. What is the crude mortality rate per 1,000 population in 2014? A. 2.05 deaths per 1,000 population in 2014 B. 2.13 per 1,000 C. 958 deaths per 1,000 population in 2014 D. 958 per 1,000 in 2014 E. 0.045 deaths per 1,000 population in 2011
A. 2.05 deaths per 1,000 population in 2014
In a study of 500 cases of a disease and 500 controls, the suspected etiological factor is found in 400 of the cases and 100 of the controls. The incidence of disease in cases with the factor is: A. 80% B. 50% C. 40% D. 20%
A. 80%
No partial credit will be awarded. A study to assess the association of diabetes and smoking compares a group of hospitalized individuals with diabetes and a group of volunteer individuals without diabetes that are employees of the same hospital where the cases were identified. The results from this study reported, for the first time in the literature, a strong association between diabetes and smoking. The magnitude of this association is likely to be due to (Check all that apply): A. Berkson's bias B. Recall bias C. Interviewer bias D. Publicity bias E. Non-response bias
A. Berkson's bias E. Non-response bias
A. Experimental B. Retrospective Cohort C. Correlational D. Prospective Cohort E. Cohort F. Ecologic G. Case-Control H. Cross-Sectional
A. Experimental
What does does this format indicate? 1.7 million : 2.5 billion A. Ratio B. Proportion C. Incidence proportion D. Mortality rate
A. Ratio
Pay particular attention here: on the End of Module Quiz, the Midterm, and the Final, you will be required to answer these types of questions in short essay format and to receive full points, you must convert your mathematical answer to a percentage and include it in your interpretation. In the previous question you were asked to calculate the relative risk for falling and getting a hip fracture if you took supplemental calcium. 1. Using correct interpretation formatting, what does your statistical relative risk answer mean? 2. What public health message would you disseminate? A. Women who took calcium supplements were 21% less likely to have a hip fracture. Calcium supplements appear to have a protective effect on preventing hip fracture. B. Women who took calcium supplements were 79% less likely to have a hip fracture. Calcium supplements appear to have a protective effect on preventing hip fracture. C. Women who took calcium supplements were 42% less likely to have a hip fracture. Calcium supplements are a good strategy to prevent hip fracture. D. Women who took calcium supplements were 0.58 times less likely to have a hip fracture. Calcium supplements are a good strategy to prevent hip fracture. E. Women who took calcium supplements were 0.45 times less likely to have a hip fracture. Calcium supplements are a good strategy to prevent hip fracture.
A. Women who took calcium supplements were 21% less likely to have a hip fracture. Calcium supplements appear to have a protective effect on preventing hip fracture.
Prevalence
All cases (new and old) in a population at risk over a specified time.
The theory that there IS an association between the exposure and the outcome.
Alternate hypothesis
The cumulative incidence rate of infection or disease in a group over a period of an epidemic calculated by dividing those who are sick by those who are sick and well. It is not a true rate because the time dimension is often uncertain.
Attack Rate
A. Relative Risk is equal to 1 (RR = 1) or Odds Ratio is equal to 1 (OR = 1) B. Odds Ratio is greater than 1 (OR > 1) C. Relative Risk is greater than 1 (RR > 1) D. Odds Ratio E. Confidence Interval F. Odds Ratio is less than 1 (OR < 1) G. Relative Risk H. Relative Risk is less than 1 (RR < 1)
B. Odds Ratio is greater than 1 (OR > 1)
Investigation of an Outbreak of Salmonella Saintpaul Infections Linked to Raw Alfalfa Sprouts. In May 2014, the CDC reported: 235 persons infected with the outbreak strain of Salmonella Saintpaul have been reported from 14 states. The number of ill persons identified in each state is as follows: Nebraska (111), Iowa (35), South Dakota (38), Michigan (19), Kansas (8), Pennsylvania (7), Minnesota (5), Ohio (3), Illinois (2), Virginia (2), West Virginia (2), Florida (1), North Carolina (1), and Utah (1). If the population of all the states combined is 127,000,000 what is the rate of infections per 100,000 persons for this study? Be careful to round only at the very end of mathematical operations. If you round earlier, it can significantly alter your answer, making it inaccurate. At the end of mathematical operations, you should round to two decimal places. It is important to not only do the math, which is one half of the answer, but to also identify the answer by using an accurate description or label. A. 1.85 Salmonella Saintpaul infections per 100,000 persons B. 0.19 Salmonella Saintpaul infections per 100,000 persons as of May 2014 C. 0.19 D. 19%
B. 0.19 Salmonella Saintpaul infections per 100,000 persons as of May 2014
Broncoville has a population of 100,000. In 2011, there 1,000 deaths in the population from all causes. There were 300 cases of tuberculosis (TB) identified. In 2011, 110 people died of TB. What is the cause-specific mortality rate per 1,000 population? Be careful to round only at the very end of mathematical operations; round to two decimal places. A. 10 TB deaths per 1,000 B. 1.10 TB deaths per 1,000 population in 2011 C. 0.0011 TB deaths per 1000 D. 0.003 per 1,000 population in 2011
B. 1.10 TB deaths per 1,000 population in 2011
Broncoville has a population of 467,443. In 2014, there 958 deaths in the population from all causes. There were 153 cases of community acquired pneumonia (PNA) identified. In 2014, 38 people died of PNA. What is the case fatality rate per 1,000 population in 2014? A. 0.25 PNA deaths per 1,000 population in 2014 B. 248.37 PNA deaths per 1,000 PNA cases in 2014 C. 2.48 PNA deaths per 1,000 population in 2014 D. 24.84 PNA deaths per 1,000 population in 2014
B. 248.37 PNA deaths per 1,000 PNA cases in 2014
An outbreak of Clostridium difficile occured in Boise, Idaho in March of 2014. The epidemic of C. difficile was investigated by local epidemiologists. In May of 2014, Central District Health reported: 2 cases of C. diff in female children ages 4-12 who used the restroom at restaurant X. 10 cases of C. diff in male children ages 4-12 who used the restroom at restaurant X. 6 cases of C. diff in female teenagers ages 13-19 who used the restroom at restaurant X. 38 cases of C. diff in male teenagers ages 13-19 who used the restroom at restaurant X. 16 cases of C. diff in female adults aged 20 and over who used the restroom at restaurant X. 26 cases of C. diff in male adults aged 20 and over who used the restroom at restaurant X. Investigators were able to locate and interview 360 females and 439 males (children and adults) who used the restroom at restaurant X in the same month who did not have C. diff. What is the attack rate in March for Boiseans? Were men or women more likely to contract C. diff? Be careful to round only at the very end of mathematical operations. If you round earlier, it can significantly alter your answer, making it inaccurate. At the end of mathematical operations, round to two decimal places. It is important to not only do the math, which is one half of the answer, but to also identify the answer by using an accurate description or label. A. Attack rate: 20.71% Males were more likely to contract C. diff B. Attack rate: 10.93% Males were more likely to contract C. diff in March 2014. C. Attack rate: 12.36% Males were more likely to contract C. diff in March 2014. D. Attack rate: 10.93% Females were more likely to contract C. diff in March 2014.
B. Attack rate: 10.93% Males were more likely to contract C. diff in March 2014.
You are an epidemiologist investigating increasing cancer rates reported in Southern California. You choose to utilize a case-control study and subsequently identify 2,000 people living in and around the town of Jericho. Three years ago, 1,000 employees of Jericho Gas & Electric were accidentally exposed to high levels of Hexavalent Chromium VI (HC6) in a hazmat spill. You compare the various cancers in these employees with that of 1,000 citizens who were not exposed to HC6. Forty-two JG&E employees exposed and three citizens not exposed to HC6 developed cancers. Using the 2 x 2 table provided, calculate the odds ratio of developing cancer for those exposed to HC6. (Formula: AD / BC) Cases of Cancer No Cancer Totals Exposed HC6 42 (a) 958 (b) 1000 Not Exposed HC6 3 (c) 997 (d) 1000 Totals 34 1966 2000 A. Cases who developed cancer were 13.87 times more likely be exposed to HC6 than controls. B. Cases who developed cancer were 14.57 times more likely to be exposed to HC6 than controls. C. Cases who developed cancer were 7.29 times more likely to be exposed to HC6 than controls. D. Cases who developed cancer were 140 times more likely to be exposed to HC6 than controls.
B. Cases who developed cancer were 14.57 times more likely to be exposed to HC6 than controls.
The California Highway Patrol statistics revealed that more accidents occurred to blue cars than to cars of any other color. The inference that while driving a blue car, one is at higher risk of accident than while driving a car of another color is: A. Correct B. Incorrect, because the comparison is not based on rates C. Incorrect, because no test of statistical significance was used D. Incorrect, because prevalence is used intead of incidence
B. Incorrect, because the comparison is not based on rates
In order to assess how strongly related an exposure is to a disease, which would be the best health statistic? A. Incidence of the disease in the exposed B. Relative risk C. Attributable risk D. Prevalence of the exposure
B. Relative risk
Investigates rare exposures in a group of subjects to determine probable causes of a disease. Researchers may use health and other official records to retrieve data from prior years or decades. A. Experimental B. Retrospective Cohort C. Correlational D. Prospective Cohort E. Cohort F. Ecologic G. Case-Control H. Cross-Sectional
B. Retrospective Cohort
Prevalence is defined as: A. The number of new cases in a population at a given time. It is calculated by dividing the number of disease cases at a specified time by the number of persons at risk for having the disease at that specifiied time. B. The number of disease cases in a population at a given time. It is calculated by dividing the disease cases at a specified time by the number of persons at risk for having the disease at that specifiied time. C. The number of new cases in a population at a given time. It is calculated by dividing the number of new disease cases at a specified time by the number of persons at risk for having the disease at that specifiied time. D. The number of disease cases in a population at a given time. It is calculated by dividing the number of new disease cases at a specified time by the number of persons at risk for having the disease at that specifiied time. E. The number of disease cases in a population. It is calculated by dividing the number of disease cases by the number of persons at risk for having the disease.
B. The number of disease cases in a population at a given time. It is calculated by dividing the disease cases at a specified time by the number of persons at risk for having the disease at that specifiied time.
Incidence is defined as: A. The number of disease cases in a population at a given time. It is calculated by dividing the number of new disease cases at a specified time by the number of persons at risk for having the disease at that specifiied time. B. The number of new cases in a population at a given time. It is calculated by dividing the number of new disease cases at a specified time by the number of persons at risk for having the disease at that specifiied time. C. The number of new cases in a population. It is calculated by dividing the number of disease cases by the number of persons at risk for having the disease. D. The number of disease cases in a population at a given time. It is calculated by dividing the disease cases at a specified time by the number of persons at risk for having the disease at that specifiied time. E. The number of new cases in a population at a given time. It is calculated by dividing the number of disease cases at a specified time by the number of persons at risk for having the diseases at that specifiied time.
B. The number of new cases in a population at a given time. It is calculated by dividing the number of new disease cases at a specified time by the number of persons at risk for having the disease at that specifiied time.
In a study designed to estimate the prevalence of hypotension (low blood pressure) among adults in an inner-city community, a sample of residents is selected for examination. Which of the following sampling methods is least likely to introduce bias? A. residents who respond to a call for volunteers in the community's weekly newspaper B. residents living in a random selection of addresses from the street directory of the community C. residents selected randomly from the records of local physicians D. residents selected randomly from the checkout lines of local grocery stores
B. residents living in a random selection of addresses from the street directory of the community
Occurs when study subjects respond to a call for cases because the topic has been in the media A. Recall Bias B. Misclassification C. Publicity Bias D. Reporting Bias E. Interviewer Bias F. Non-Response Bias G. Berkson's (Hospital Admission Rate) Bias H. Exclusion Bias
C. Publicity Bias
There is a larger incidence of disease (outcome) in the exposed than in the unexposed. Exposure appears to increase the probability of developing the disease (outcome). It shows a positive relationship between exposure and outcome. A. Relative Risk is equal to 1 (RR = 1) or Odds Ratio is equal to 1 (OR = 1) B. Odds Ratio is greater than 1 (OR > 1) C. Relative Risk is greater than 1 (RR > 1) D. Odds Ratio E. Confidence Interval F. Odds Ratio is less than 1 (OR < 1) G. Relative Risk H. Relative Risk is less than 1 (RR < 1)
C. Relative Risk is greater than 1 (RR > 1)
In a recent study of dental erosion in 5-year-old children, 202 healthy school-attending children were selected for study. The investigators recorded the erosion level on their maxillary deciduous incisors and whether or not their communities used fluoridated water. The results are summarized in the table below: Dental Erosion in 5-Year-Old Children Evidence of Erosion No Evidence of Erosion Total Fluori- 46(a) 30(b) 76 dated Area Non- fluori- 77(c) 37(d) 114 dated Area Total 123 67 190 What is the incidence rate of erosion for the fluoridated group of children? (You may assume their teeth were free of erosion at birth.) Be careful to round only at the very end of mathematical operations; round to two decimal places. A. 0.68 new cases of dental erosion in the non-floridated area B. 0.01 new cases C. 0.61 new cases of dental erosion in the floridated area D. 0.89 cases of dental erosion in the floridated group
C. 0.61 new cases of dental erosion in the floridated area
Broncoville has a population of 467,443. In 2014, there 958 deaths in the population from all causes. There were 153 cases of community acquired pneumonia (PNA) identified. In 2014, 38 people died of PNA. What is the cause-specific mortality rate per 100,000 population in 2014? A. 994 PNA deaths per 100,000 in 2014 B. 0.00081 deaths from PNA per 100,000 population in 2014 C. 8.13 deaths from PNA per 100,000 population in 2014 D. 812 PNA deaths per 100,000 population in 2011
C. 8.13 deaths from PNA per 100,000 population in 2014
Five years after the introduction of a vigorous detection program, the prevalence of diabetes mellitus was found to be greater than in the year prior to the introduction of the program. Which of the following are possible reasons? A. An increase in diabetes case fatality B. An increase in age-specific mortality associated with diabetes C. An increase in previously undetected cases D. An increase in the proportionate mortality associated with diabetes E. A reduction in the risk factors predisposing people to diabetes
C. An increase in previously undetected cases
Pay particular attention here: on the End of Module Quiz, the Midterm, and the Final, you will be required to answer these types of questions in short essay format. In the previous question you were asked to calculate the relative risk for developing obesity if you ate out often. 1. Using correct interpretation formatting, what does your statistical relative risk answer mean? 2. What public health message would you disseminate? A. People who primarily eat out are 1.83 times less likely to be obese than those who primarily eat at home. Eating out often is good health strategy to prevent obesity. B. People who primarily eat out are 1.83 times more likely to be obese than those who primarily eat at home. Eating at home is a good health strategy to prevent obesity. C. People who primarily eat out are 2.88 times more likely to be obese than those who primarily eat at home. Eating at home is a good health strategy to prevent obesity. D. People who are obese are 2.88 times more likely to eat out. Eating out is a good health strategy to prevent obesity. E. People who primarily eat out are 2.87 times more likely to be obese than those who primarily eat at home. Eating at home is a good health strategy to prevent obesity.
C. People who primarily eat out are 2.88 times more likely to be obese than those who primarily eat at home. Eating at home is a good health strategy to prevent obesity.
What does does this format indicate? 7 : 2 A. Incidence proportion B. Mortality rate C. Ratio D. Proportion
C. Ratio
Prevalence is defined as: A. The number of new cases in a population at a given time. It is calculated by dividing the number of new disease cases at a specified time by the number of persons at risk for having the disease at that specified time. B. The number of new cases in a population at a given time. It is calculated by dividing the number of disease cases at a specified time by the number of persons at risk for having the disease at that specified time. C. The number of disease cases in a population at a given time. It is calculated by dividing the disease cases at a specified time by the number of persons at risk for having the disease at that specified time. D. The number of disease cases in a population at a given time. It is calculated by dividing the number of new disease cases at a specified time by the number of persons at risk for having the disease at that specified time. E. The number of disease cases in a population. It is calculated by dividing the number of disease cases by the number of persons at risk for having the disease.
C. The number of disease cases in a population at a given time. It is calculated by dividing the disease cases at a specified time by the number of persons at risk for having the disease at that specified time.
In 1945, 1,000 women worked in a factory painting radium dials on watches. The incidence of bone cancer in these women up to 1975 was compared with that of 1,000 women who worked as telephone operators in 1945. Twenty of the radium dial workers and four of the telephone operators developed bone cancer between 1945 and 1975. Develop a 2 x 2 table and determine relative risk of developing bone cancer for radium dial workers: A. Women who worked in the radium dial watch factory were 2 times more likely to get bone cancer than those who were telephone operators during the same time period. Working at the radium dial watch factory was not a good career choice. B. Women who worked in the radium dial watch factory were 2 times less likely to get bone cancer than those who were telephone operators during the same time period. Working at the radium dial watch factory was a good career choice. C. Women who worked in the radium dial watch factory were 5 times more likely to get bone cancer than those who were telephone operators during the same time period. Working at the radium dial watch factory was not a good career choice. D. Women who worked in the radium dial watch factory were 5 times less likely to get bone cancer than those who were telephone operators during the same time period. Working at the radium dial watch factory was a good career choice.
C. Women who worked in the radium dial watch factory were 5 times more likely to get bone cancer than those who were telephone operators during the same time period. Working at the radium dial watch factory was not a good career choice.
Key elements in descriptive epidemiology for "time"
Calendar days, hours in a day, monthly/yearly cycles of climate
In Australia on December 31, 1995, there were 4,494 dialysis patients and 4,209 transplant-dependent patients. At that time, there were approximately 9.3 million citizens in Australia. a. What is the prevalence rate for dialysis patients [1]? b. What is the prevalence rate per million transplant-dependent patients [2]? Place a zero before the decimal point and round to two decimal places (ie: 0.012). Submit only numbers, no text.
[1] 0.00048 [2] 452.58
Broncoville is a very unsafe town. Its residents do not like wearing seatbelts and there is no law requiring seatbelts be worn. Approximately 50% of Broncoville residents refuse to wear a seat belt. Among those who wear seatbelts consistently, the incidence of death in motor vehicle accidents is 2.6 deaths per 10,000. The incidence of death from motor vehicle accidents among Broncoville residents who did not wear a seat belt is 10.6 deaths per 10,000. A. Calculate the relative risk RR of death among non-seatbelt users versus seatbelt users. [1] B. Calculate the attributable risk (AR) of not using a seatbelt on death in a motor vehicle accident. [2] Enter only numbers into your answer. If the answer is in decimal form, place a leading 0 in front of the decimal (ie: 0.89). Round to two decimal places after completing mathematical operations. For part B, I will assume you are expressing this as a percent: do NOT place a % sign after your answer).
[1] 4.08 [2] 60.63
In Broncoville on May 31st, 2014 there were 308,958 dialysis patients and 4,602 transplant-dependent patients. At that time, there were approximately 5.7 million citizens in Broncoville. a. What is the prevalence rate per 100 for dialysis patients [1]? b. What is the prevalence rate per 100,000 transplant-dependent patients [2]? Place a zero before the decimal point and round to two decimal places (ie: 0.11) or two significant digits (ie 0.0011). Submit only numbers, no text.
[1] 5.42 [2] 80.74
State Vital Statistics
births, deaths, marriages, divorces
Most case reports are investigated by public health workers in order to: a. none of these answers b. treat the affected person appropriately c. understand the underlying risk factors present d. develop a vaccine
c. understand the underlying risk factors present
Between January 2005 and May 2007, the CDC had identified 138 cases of Acanthomelobe Keratitis infections (a rare but potentially blinding infection of the cornea of the eye) in 35 states and Puerto Rico. Although only 46 interviews of infected individuals have been acquired, the results indicate a linkage to the use of Complete MoisturePlus Multipurpose contact lens solution. How might public health officials have handled this outbreak? a. Official letters to all registered healthcare practitioners announcing methods of treatment and follow-up b. Provide the option to health care providers to report the disease c. Public health announcement d. All of the above
d. All of the above
Just recently, a rising incidence of renal failure in dogs was eventually linked to tainted dog food. What might have investigators used to help determine the origin of this outbreak? a. Epi curve b. Survey c. Plot map d. Both a and c
d. Both a and c
Public health surveillance is used to:
d. all of these things
If you wanted to collect data to calculate a mortality rate, which source from the list below would make the most sense? a. hospitals b. laboratory reports c. disease registry d. death certificates
death certificates
Be sure your spelling is correct. The three components of the epidemiologic triad are [a], [b], and [c].
environment, host, agent
Behavioral Risk Factor Surveillance System
prevalence of chronic diseases
The ultimate goal of epidemiology is to [x] and [y] disease in populations. A. encourage and promote B. prevent and concede C. stop and control D. prevent and limit E. prevent and control
prevent and control
Census
race, gender, age, marital status
All proportions are ratios, but not all ratios are proportions. True or False?
rue
Outbreaks may encompass any time period or time frame. True or False?
true