HSC 404 - Final Exam (Ch 9, 10, 11, 12, 13, 15, 16)

An outbreak of salmonellosis occurred after an epidemiology department luncheon, which was attended by 485 faculty and staff. Assume everyone ate the same food items. Sixty-five people had fever and diarrhea, five of these people were severely affected. Subsequent laboratory tests on everyone who attended the luncheon revealed an additional 72 cases. The attack rate of salmonellosis was:

28.2%

An outbreak of salmonellosis occurred after an epidemiology department luncheon, which was attended by 485 faculty and staff. Assume everyone ate the same food items. Sixty-five people had fever and diarrhea, five of these people were severely affected. Subsequent laboratory tests on everyone who attended the luncheon revealed an additional 72 cases. The ratio of severe cases to other clinically apparent cases was:

5/60

A new screening test for Lyme disease is developed for use in the general population. The sensitivity and specificity of the new test are 60% and 70%, respectively. Three hundred people are screened at a clinic during the first year the new test is implemented. Assume the true prevalence of Lyme disease among clinic attendees is 10%. The number of false positives is: A. 81 B. 9 C. 2,162 D. 99 E. 12

A

A screening examination was performed on 250 persons for Factor X, which is found in disease Y. A definitive diagnosis for disease Y among the 250 persons had been obtained previously. The results are charted below: The specificity of this test is expressed as: A. 70% B. 56% C. 7% D. 80% E. 30%

A

A test that determines whether disease is actually present is a: A. Diagnostic test B. Screening test C. Reliability test D. None of the above

A

Exposure to electric and magnetic fields have been linked to: A. Childhood leukemia risk B. Lung Cancer C. Central Nervous System damage D. All of the above

A

One must use care in interpreting occupational differences in morbidity and mortality because: A. Good health status may be a factor for selection fo job B. Occupations involving physical activity tend to cause heart attacks among older workers C. Occupational stress, even in extreme situations, is difficult to quantify D. All of the above

A

Personal behavior and lifestyle factors in health do NOT include: A. Social support B. Alcohol consumption C. Dietary practices D. Lack of exercise

A

Recall bias is most likely to occur in: A. Case control studies B. Prospective cohort studies C. Experimental studies D. All of the above E. None of the above

A

The Centers for Disease Control and Prevention published an article concerning the high rate of foot fungal disease in New Orleans. The article explains that there has been a high rate of foot fungal disease in New Orleans for decades. Foot fungal disease in New Orleans is best described as: A. Endemic B. Incident C. Pathogenic D. Epidemic

A

Which of the following conditions would not be likely to be considered a Western or way-of-life disease? A. Bacterial infections B. Diverticular disease C. Obesity D. Diabetes E. Gallbladder disease

A

What is synergism?

A situation in which the combined effect of several exposures is greater than the sum of the individual effects

In a case-control study of the relationship of radiation exposure and thyroid cancer, 50 cases admitted for thyroid cancer and 100 "controls" admitted during the same period for treatment of hernias were studied. Only the cases were interviewed, and 20 of the cases were found to have been exposed to x-ray therapy in the past, based on the interviews and medical records. The controls were not interviewed, but a review of their hospital records when they were admitted for hernia surgery revealed that only 2 controls had been exposed to x-ray therapy in the past. Based on the description, what source of bias is least likely to be present in this study?

A. Bias due to controls being non representative of the non diseased population B. Bias due to use of different methods of ascertainment of exposure in the cases and controls C. Bias due to loss of subjects from control groups over time D. Recall bias E. Selection bias for exposure to x-ray therapy in the pat C

You are investigating the role of physical activity in heart disease and suggest that physical activity protects against having a heart attack. While presenting these data to your colleagues, someone asks if you have thought about confounders such as factor X. This factor X could have confounded your interpretation of the data if it:

A. Is a factor associated with physical activity and heart disease B. Is a factor for some other disease, but not heart disease C. Has caused a lack of follow-up of test subjects D. Is a part of the pathway by which physical activity affects heart disease A

A person with an inapparent infection:

A. Is of no epidemiological importance B. Is a danger to family members but not to others in the community C. Can transmit the infection to other

A new antibody test detects serum antibodies against virus X (sensitivity 99%, specificity 90%). When applied in a group of hospitalized patients diagnosed as having virus X infections, the test is found to have a positive predictive value of 85%. When used to screen a group of healthy blood donors for virus X infections, the test is found to have a positive predictive value of 30%. Which of the following best explains this difference between the positive predictive values?

A. Measurement error was introduced into the procedure B. Lead time bias occurs among the blood donors C. Cases of virus X infection are more severe on the hospital D. The prevalence of virus X infection is higher among the hospital patients than among blood donors

An epidemiologic experiment is performed in which one group is exposed to a suspected factor and the other is not. All individuals with an odd hospital admission number are assigned to the second group. The main purpose of this procedure is to:

A. Prevent observer bias with respect to the factor B. Prevent observer bias with respect to the outcome C. Improve the likelihood that the two groups will be comparable with regard to known and unknown confounding factors. D. Ensure a double-blind study E. Guarantee comparability of the two groups with regard to other relevant factors C

Surgeons at Hospital A report that the mortality rate at the end of a one-year follow-up after a new coronary bypass procedure is 15%. At Hospital B, the surgeons report a one-year mortality rate of 8% for the same procedure. Before concluding that the surgeons at Hospital B have vastly superior skill, which of the following possible confounders would you examine?

A. The severity (stage) of the disease of the patients at the two hospitals at baseline B. The starting point of the one-year follow-up at both hospitals C. Different in the post-operative care at the two hospitals D. Equally through follow-up for mortality E. All of the above E

What three factors comprise the epidemiologic triangle?

Agent, host, & environment

A screening examination was performed on 250 persons for Factor X, which is found in disease Y. A definitive diagnosis for disease Y among the 250 persons had been obtained previously. The results are charted below: TEST RESULTS Disease Present Disease Absent Positive for Factor X 40 60 Negative for Factor X 10 140 The sensitivity of this test is expressed as: A. 7% B. 80% C. 56% D. 70% E. 30%

B

A sentinel health event refers to: A. The correlation between daily mortality and increased air pollution B. A case of unnecessary workplace disease serves as a warning signal C. The nuclear plant accident in Chernobyl, Ukraine D. None of the above

B

Asbestos exposure has been associated with: A. Pesticides from the organochloride family B. Asbestosis, malignant mesothelioma, and lung cancer C. Metallic compounds D. Vinyl chloride

B

Drs. Poke and Jab (2014) conducted an employee health program that used 5 screening tests at the same time to detect diseases among workers. Which type of program is this? A. Mass screening B. Multiphasic screening C. Selective screening D. Ad hoc screening

B

Selye's concept of the general adaptation syndrome did NOT include: A. Alarm reaction B. Stage of recovery C. Stage of resistance D. State of exhaustion

B

The type A behavior pattern is hypothesized: A. Chronic obstructive pulmonary disease B. Coronary heart disease C. Rheumatoid arthritis D. All of the above

B

An outbreak of salmonellosis occurred after an epidemiology department luncheon, which was attended by 485 faculty and staff. Assume everyone ate the same food items. Sixty-five people had fever and diarrhea, five of these people were severely affected. Subsequent laboratory tests on everyone who attended the luncheon revealed an additional 72 cases. The virulence of salmonellosis was:

B. 47.4%

A new blood test has been developed to screen for disease Z. Researchers establish 50 units as a cut point above which a test is considered positive and thereby indicative of disease. The test manufacturers determine that the test's sensitivity is unacceptably low. However, the manufacturers are not concerned with the specificity and do not want the cost of the test to rise. How can they improve the sensitivity of the test? A. Raise the cut point above 50 units B. They cannot improve the test and should begin work developing a new test C. Lower the cut point below 50 units D. Test each person's blood twice

C

In a study to determine the incidence of chronic disease, 150 people were examined at the end of a three-year period. Twelve cases were found, giving a cumulative risk of 8%. Fifty other members of the initial cohort could not be examined; 20 of these 50 could not be examined because they died. Which source of bias may have affected the study? A. Information bias: interviewer/abstractor bias B. Hawthorne Effect C. Selection bias: survival bias D. Information bias: recall bias

C

The public health officer from Long Beach complains to you about the dreaded Pacific Pox. The health officer says, "If people catch the Pox, they suddenly get the urge to dance in the sand and fall dead on the beach within the hour." There are no survivors to interview so you deduce: A. The infectivity of the Pox must be high B. All of the above C. The case fatality rate of the Pox must be high D. The prevalence of the Pox must be high E. The incidence rate of the Pox must be high

C

With respect to a hypothetical rabies investigation conducted among veterinary workers (Dr. Spot, 2003), researchers found that rabies was almost always fatal. This finding refers to: A. Antigenicity B. Infectivity C. Virulence D. Toxigenicity

C

Examples of social incongruity include: A. Discrepancy between parents in social status B. Discrepancy between generations, e.g., fathers, and sons C. Changes from rural to urban residence D. All of the above

D

Sociocultural influences on health include: A. Specific behaviors associated with daily living B. Mediation of stress exposure C. Health services utilization D. All of the above

D

Someone suggests immunization as a means of reducing disease, specifically the feared UJ (uderlinger jacamoodi). What part of the disease cycle is he or she trying to affect? A. Environment B. Fomites C. Vector D. Host E. Vehicle

D

The degree of agreement among several trained experts refers to: A. Concurrent validity B. Repeated measures C. Internal consistency D. Inter-judge reliability

D

The most important methodological problems in the measurement of life events are: A. Subject's recall ability B. Reliability of measurement C. Memory Biases D. A, B, and C E Number of items in the questionnaire

D

The purpose of a double-blind study is to: A. Reduce the effects of sampling variation B. Avoid observer bias and sampling variation C. Achieve comparability of cases and controls D. Avoid observer and interviewee bias E. Avoid interviewee bias and sampling variation

D

The site where a disease agent enters the body is the: A. Portal of exit B. Reservoir C. Vehicle D. Portal of entry

D

The strategy which is not aimed at reducing selection bias is: A. Development of an explicit case definition B. Standardized protocol for structured interviews C. Enrollment of all cases in a defined time and region D. Encouragement of high participation rates

D

Which of the following is not a type of selection bias in cohort studies: A. Loss to follow-up B. None of the above C. Healthy worker effect D. Interviewer bias

D

Lead time bias is best described as:

D. An apparently lower survival rate among persons screened compared to an unscreened group.

A new screening test for Lyme disease is developed for use in the general population. The sensitivity and specificity of the new test are 60% and 70%, respectively. Three hundred people are screened at a clinic during the first year the new test is implemented. Assume the true prevalence of Lyme disease among clinic attendees is 10%. The predictive value of a positive test is: A. 6.0% B. 33% C. 22.2% D. 94% E. 18.2%

E

According to the Association of School of Public Health, competences in epidemiology to be achieved by Master of Public Health degree candidates in public health include: A. Evaluating the strengths and limitations of epidemiological reports B. Calculating basic epidemiology measures C. Communicating epidemiologic information to lay and processional audiences D. A and B only E. All of the above

E

Career roles for epidemiologist include: A. Academic works and healthcare planners B. Council of states and territorial epidemiologists employment listing C. Disease surveillance D. Researchers E. All of the above

E

Social epidemiology deals with the health effects of: A. Socioeconomic stratification B. Social networks C. Discrimination D. Work demands E. All of the above

E

Which of the following is not a method for controlling the effects of confounding in epidemiologic studies? A. Matching B. Randomization C. Stratification D. Restriction E. Blinding

E

Which of the following is the leading source of radiation? A. Consumer products B. Medical X-rays C. Nuclear medicine D. Terrestrial E. Radon

E

Which of the following statements describes a stressful life event? A. Discrepancy between husband and wife in social and educational status B. Goodness of fit between characteristics of the person and environment C. Occurrence that might cause read adjustments in people's activities D. None of the above

E.

T or F: The field of epidemiology is restricted to only 30 specializations.

False

Healthy persons are more likely to gain employment than unhealthy persons is called

The healthy worker effect

What is the threshold?

The lowest dose at which a particular response may occur

What is latency?

The time period between initial exposure and a measurable response

T or F: Education in epidemiology can be obtained via special summer session program and online programs.

True

T or F: The Epidemiology Monitor is a newsletter that lists employment opportunities in national and international locations.

True