Chapter 12: Epidemiology

A nurse examines birth and death certificates during an epidemiologic investigation. Which of the following data categories is being used? a. Routinely collected data b. Data collected for other purposes but useful for epidemiologic research c. Original data collected for specific epidemiologic studies d. Surveillance data

A Birth and death certificates are considered to be vital records and are examples of data collected routinely. Data collected for other purposes would be hospital, physician, health department, laboratory, and insurance records. Original data is that which is collected by the National Center for Health Statistics for specific health surveys. Surveillance data is used to assess and prioritize the health needs of populations, design public health and clinical services to address those needs, and evaluate the effectiveness of public health programs.

As a result of an outbreak of influenza in a community, a nurse encourages members of the community to receive the influenza vaccine. Which of the following levels of prevention is being used? a. Primary prevention b. Secondary prevention c. Tertiary prevention d. Multifactorial prevention

A Nurses are involved in epidemiologic surveillance by monitoring the potential for disease outbreaks. Primary prevention refers to interventions aimed at preventing the occurrence of disease, injury, or disability. Immunizations are an example of primary prevention. Secondary prevention interventions are designed to increase the probability that a person with a disease will have that condition diagnosed at a stage when treatment is likely to result in cure. Tertiary prevention includes interventions aimed at disability limitation and rehabilitation from disease, injury, or disability. Multifactorial prevention is not possible with a disease like influenza, which has one cause.

A PHN conducts an immunization clinic for measles. Which of the following is being implemented? a. Primary prevention b. Secondary prevention c. Tertiary prevention d. Health promotion

A Primary prevention refers to those interventions aimed at preventing the occurrence of disease, injury, or disability. Immunizations are an example of primary prevention. Secondary prevention interventions are designed to increase the probability that a person with a disease will have that condition diagnosed at a stage when treatment is likely to result in cure. Tertiary prevention includes interventions aimed at disability limitation and rehabilitation from disease, injury, or disability. Health promotion is a specific primary prevention strategy.

An intervention that focuses on the tertiary level of prevention is implemented by the nurse? Which of the following did the nurse most likely complete? a. Rehabilitative job training b. Parenting education c. Testicular self-examination d. Family counseling

A Tertiary prevention includes those interventions aimed at disability limitation and rehabilitation from disease, injury, or disability. Rehabilitative job training would be an example of tertiary prevention. Parenting education is an example of primary prevention. Testicular self-examination and family counseling are examples of secondary prevention.

The most important predictor of overall mortality is: a. race. b. age. c. gender. d. income.

B The mortality curve by age drops sharply during and after the first year of life to a low point in childhood, then begins to increase through adolescence and young adulthood and then increases sharply through middle and older ages. Race, gender, and income are not the most important predictor for overall mortality.

The type of epidemiologic study that is used to describe a group of persons enrolled in a study who share some characteristic of interest and who are followed over a period of time to observe some health outcome is a(n): a. case-control study. b. cross-sectional study. c. cohort study. d. experimental study.

C A cohort study is the type of epidemiologic study that is used to describe a group of persons enrolled in a study who share some characteristic of interest and who are followed over a period of time to observe some health outcome. A case-control study uses a sample from the cohort rather than following the entire cohort over time. A cross-sectional study provides a snapshot of a population or group at one point in time. An experimental study is one in which the investigator initiates some treatment or intervention that may influence the risk or course of the disease.

A public health nurse (PHN) reports an attack rate. Which of the following has most likely been reported? a. Number of cases of cancer recorded at a medical center b. Number of people who died of Ebola in a given year c. Number of beef cattle inoculated against mad-cow disease on a farm d. Proportion of people becoming ill after eating at a fast-food restaurant

D Attack rates are often specific to exposures, such as food-specific attack rates. The number of cases of cancer, exposure to Ebola, and beef cattle are not significant without knowing the total number of people so that a proportion can be calculated.

The factors, exposures, characteristics, and behaviors that determine patterns of disease are described using: a. descriptive epidemiology. b. analytic epidemiology. c. distribution. d. determinants.

D Determinants are the factors, exposures, characteristics, and behaviors that determine patterns of disease, which may be individual, relational, social, communal, or environmental. Descriptive epidemiology seeks to describe the occurrence of a disease in terms of person, place, and time. Analytic epidemiology focuses on the investigation of causes and associations. Distribution describes who has the disease and where and when the disease occurs.

To understand the causes of health and disease, epidemiology studies: a. individuals. b. families. c. groups. d. populations.

D Epidemiology monitors health of populations, understands determinants of health and disease in communities, and investigates and evaluates interventions to prevent disease and maintain health. Epidemiology does not focus on individuals, families, and groups.

A study that uses information on current health status, personal characteristics, and potential risk factors or exposures all at once is called: a. cross-sectional. b. ecological. c. case-control. d. cohort.

A A cross-sectional study collects information on current health status, personal characteristics, and potential risk factors or exposures all at once. A cohort study is the type of epidemiologic study that is used to describe a group of persons enrolled in a study who share some characteristic of interest and who are followed over a period of time to observe some health outcome. An ecological model considers the multiple factors that contribute to disease development.

John Snow is called the "father of epidemiology" because of his work with: a. cholera. b. malaria. c. polio. d. germ theory.

A John Snow investigated the spread of cholera in the mid-nineteenth century. John Snow did not investigate the other examples.

Which statement is true about mortality rates? Mortality rates: a. are informative only for fatal diseases. b. provide information about existing disease in the population. c. are calculated using a population estimate at year-end. d. reveal the risk of getting a particular disease.

A Mortality rates are informative only for fatal diseases and do not provide direct information about the level of existing disease or the risk of getting a particular disease. Because the population changes during the course of a year, typically an estimate of the population at midyear is taken as the denominator for annual rates, because the midyear population approximates the amount of person-time contributed by the population during a given year.

A screening for diabetes revealed 20 previously diagnosed diabetics and 10 probable new cases, which were later confirmed, for a total of 30 cases. Which of the following best describes what is being measured? a. Prevalence b. Incidence c. Attack rate d. Morbidity rate

A Prevalence is the measure of existing disease in a population at a particular time. Incidence quantifies the rate of development of new cases in a population at risk, whereas an incidence proportion indicates the proportion of the population at risk who experience the event over some period of time. Attack rate is defined as the proportion of persons who are exposed to an agent and develop the disease. Morbidity rate is the incidence of disease.

A nurse is studying the characteristics of an agent as part of the epidemiologic triangle. Which of the following is the nurse most likely studying? a. Human population distribution b. Salmonella c. Genetic susceptibility d. Climate

B An agent includes infectious organisms, such as Salmonella, chemical agents, and physical agents. Genetic susceptibility is considered to be a characteristic of a host. Human population distribution and climate are considered to be characteristics of the environment.

An epidemiologist wants to know what caused severe diarrhea and vomiting in several people at a local banquet. Which of the following principles is being applied in this situation? a. Descriptive epidemiology b. Analytic epidemiology c. Distribution d. Determinants

B Analytic epidemiology is directed toward understanding the etiology of the disease. Descriptive epidemiology seeks to describe the occurrence of a disease in terms of person, place, and time. Distribution describes who has the disease and where and when the disease occurs. Determinants are the factors, exposures, characteristics, and behaviors that determine patterns of disease, which may be individual, relational, social, communal, or environmental.

A nurse states that she has been reading about an epidemic that has been occurring in the world. Which of the following is she most likely referring to? a. "Bird" flu in China b. Adult obesity in the United States c. An isolated case of smallpox in Africa d. The nursing shortage in the United States

B It is estimated that 30% of the adults in the United States are obese. According to the Centers for Disease Control and Prevention, this is an epidemic. The other examples are not epidemics.

A nurse is investigating an outbreak of a gastrointestinal illness from a food-borne pathogen. Which of the following terms is being applied? a. Attack rate b. Point epidemic c. Secular trend d. Event-related cluster

B One temporal and spatial pattern of disease distribution is the point epidemic. A point epidemic is most clearly seen when the frequency of cases is plotted against time. The sharp peak characteristic of such graphs indicates a concentration of cases in some short interval of time. Attack rate is defined as the proportion of persons who are exposed to an agent and develop the disease. Secular trends are long-term patterns of morbidity or mortality rates. Event-related clusters are patterns in which time is not measured from fixed dates on the calendar but from the point of some exposure or event, presumably experienced in common by affected persons, although not occurring at the same time.

The probability an event will occur within a specified period of time is called: a. rate. b. risk. c. epidemiology. d. epidemic.

B Risk is the probability an event will occur within a specified period of time. Rate is a measure of the frequency of a health event in a defined population, usually in a specified period of time. Epidemiology is the study of the occurrence and distribution of health-related states or events in specified populations, including the study of the determinants influencing such states, and the application of this knowledge to control the health problems. Epidemic occurs when the rate of disease, injury, or other condition exceeds the usual level of that condition.

A nurse offers a screening for hearing defects at a local community center. Which of the following best describes the action of the nurse? a. Primary prevention b. Secondary prevention c. Tertiary prevention d. Health promotion

B Secondary prevention focuses on early detection and prompt treatment of disease, injury, or disability. Screenings are part of secondary prevention interventions. Primary prevention refers to interventions aimed at preventing the occurrence of disease, injury, or disability. Tertiary prevention includes interventions aimed at disability limitation and rehabilitation from disease, injury, or disability. Health promotion is a specific primary prevention strategy.

A nurse is considering the potential for selection bias. Which of the following best describes the situation that is the nurse has encountered? a. Determining the population to be studied b. Considering how the participants will enter the study c. Studying cause and effect relationships d. Documenting results of the study

B Selection bias is attributable to the way subjects enter a study. It has to do with selection procedures and the population from which subjects are drawn. Determining the population to be studied relates to the design of the study. Studying cause and effect relationship has to do with ecological studies. Documenting the results of the study is completed at the end of the study after the participants have been selected.

A nurse states that he has incorporated epidemiology into his practice and functions in epidemiologic roles. Which of the following best describes the actions taken by the nurse? (Select all that apply.) a. Policy making b. Collection, reporting, analysis, and interpretation of data c. Environmental risk communication d. Documentation on patient charts and records e. Law enforcement

B, C, D Collection, reporting, analysis, and interpretation of data, environmental risk communication, and documentation on patient charts and records are examples of the use of epidemiology in practice. Policy making and law enforcement do not apply to epidemiology.

During the twentieth century, a nurse participated in research that examined the epidemiology of various diseases. Which of the following best describes the factors that influenced these studies? (Select all that apply.) a. Increasing rate of poverty b. Declining child mortality rates c. Overcrowding in major cities d. Development of new vaccinations e. Advancements in medical equipment

B, D Factors contributing to the development and application of epidemiologic methods in the twentieth century were: improved nutrition, new vaccines, better sanitation, the advent of antibiotics and chemotherapies, and declining infant and child mortality and birth rates. A rise in the standard of living occurred for many following the Great Depression and World War II. The advancements in medical technology have not influenced the examination of the epidemiology of various diseases.

Voters have recently decided to have fluoride added to the city water system. Epidemiologists now want to study the effect of fluoride on dental caries in this population. Which of the following would be conducted by the epidemiologists? a. Ecological study b. Double-blind study c. Community trial d. Screening

C A community trial is similar to a clinical trial, but the issue is often health promotion and disease prevention rather than treatment of existing disease. An ecological model considers the multiple factors that contribute to disease development. A double-blind study is one in which neither the subject nor the investigator knows who is receiving the treatment. A screening involves the testing of groups of individuals who are at risk for a certain condition but are not yet symptomatic.

A nurse who is studying chronic disease considers the multifactorial etiology of illness. What does this imply? a. Genetics and molecular structure of disease is paramount. b. Single organisms that cause a disease, such as cholera, must be studied in more detail c. Focus should be on the factors or combinations and levels of factors contributing to disease. d. The recent rise in infectious disease is the main focus.

C Multifactorial etiology implies a focus on combinations and levels of factors. There are many factors to consider other than only genetics or single organisms with multifactorial etiologies. The focus of studying multifactorial etiology is on chronic disease.

The proportion of persons with positive test results who actually have a disease, interpreted as the probability that an individual with a positive test result has the disease, is the: a. sensitivity. b. specificity. c. positive predictive value. d. negative predictive value.

C Positive predictive value refers to the proportion of persons with positive test results who actually have the disease, interpreted as the probability that an individual with a positive test result has the disease. Sensitivity quantifies how accurately the test identifies those with the condition or trait. Specificity indicates how accurately the test identifies those without the condition or trait. Negative predictive value is the proportion of persons with a negative test who are actually disease free.

A PHN implements a primary prevention intervention in the community. Which of the following is most likely being implemented? a. Pap smear b. Blood pressure screening c. Diet and exercise d. Physical therapy

C Primary prevention refers to those interventions aimed at preventing the occurrence of disease, injury, or disability. Blood pressure screening and pap smears are secondary prevention interventions. Physical therapy is a tertiary prevention intervention.

A nurse is told that a screening test has high specificity. Which of the following is the best interpretation of this information? a. The test provides precise and consistent readings. b. The test accurately identifies those with the condition or trait. c. The test accurately identifies those without the trait. d. The test has a high level of false positives.

C Specificity refers to the test accurately identifying those without the trait. High specificity is needed when rescreening is impractical and when reduction of false positives is important. The test would have a low level of false positives.

A nurse refers a client with a neuromuscular disease to a vocational rehabilitation program. Which of the following best describes the action of the nurse? a. Primary prevention b. Secondary prevention c. Tertiary prevention d. Health promotion

C Tertiary prevention includes those interventions aimed at disability limitation and rehabilitation from disease, injury, or disability. Referral of a client with a disease is an example of tertiary prevention. Primary prevention refers to interventions aimed at preventing the occurrence of disease, injury, or disability. Secondary prevention focuses on early detection and prompt treatment of disease, injury, or disability. Health promotion is a specific primary prevention strategy.

Public health professionals refer to three levels of prevention as tied to specific stages in the: a. epidemiologic triangle. b. web of causation. c. natural history of disease. d. surveillance process.

C The natural history of disease is the course of the disease process from onset to resolution. The three levels of prevention provide a framework commonly used in public health practice to depict this process. The epidemiologic triangle consists of the interaction between an agent, a host, and the environment. The web of causality reflects the more complex interrelationship among the numerous factors interacting, sometimes in subtle ways, to increase (or decrease) risk of disease. The surveillance process involves the systematic collection, analysis, and interpretation of data related to the occurrence of disease and the health status of a given population.

A nurse is investigating a serious epidemic of influenza. Which of the following best describes the amount of cases that are being examined? a. 50 cases b. 100 cases c. 500 cases d. Unable to determine

D One cannot tell the degree of seriousness without a denominator, which represents the total population.

A nurse implements a program that focuses on secondary prevention. Which of the following is most likely the topic of this program? a. Rehabilitation b. Avoidance of high-risk behaviors c. Immunization d. Mammogram

D Secondary prevention focuses on early detection and prompt treatment of disease, injury, or disability. Mammograms are a screening test. Avoidance of high-risk behaviors and immunizations are examples of primary prevention. Rehabilitation is an example of tertiary prevention.

The interaction between an agent, a host, and the environment is called: a. natural history of disease. b. risk. c. web of causality. d. the epidemiologic triangle.

D The epidemiologic triangle consists of the interaction between an agent, a host, and the environment. The natural history of disease is the course of the disease process from onset to resolution. Risk is the probability an event will occur within a specified period of time. The web of causality reflects the more complex interrelationship among the numerous factors interacting, sometimes in subtle ways, to increase (or decrease) risk of disease.