Vocab

Question 0

a factor (e.g., a microorganism or chemical substance) or form of energy whose presence, excessive presence, or in the case of deficiency diseases, relative absence is essential for the occurrence of a disease or other adverse health outcome

Answer 0

agent

Question 1

any of a variety of proteins in the blood that are produced in response to an antigen as an immune response

Answer 1

antibody

Question 2

any substance (e.g., a toxin or the surface of a microorganism or transplanted organ) recognized as foreign by the human body and that stimulates the production of antibodies

Answer 2

antigen

Question 3

any of a group of viruses that are transmitted between hosts by mosquitoes, ticks, and other arthropods

Answer 3

arbovirus

Question 4

the statistical relation between two or more events, characteristics, or other variables

Answer 4

association

Question 5

a form of incidence that measures the proportion of persons in a population who experience an acute health event during a limited period (e.g., during an outbreak), calculated as the number of new cases of a health problem during an outbreak divided by the size of the population at the beginning of the period, usually expressed as a percentage or per 1,000 or 100,000 population

Answer 5

attack rate

Question 6

a measure of the frequency of new cases of a disease among the contacts of known patients

Answer 6

secondary attack rate

Question 7

systematic difference in the collection of data regarding the participants in a study (e.g., about exposures in a case-control study, or about health outcomes in a cohort study) that leads to an incorrect result (e.g., risk ratio or odds ratio) or inference

Answer 7

information bias

Question 8

systematic difference in the enrollment of participants in a study that leads to an incorrect result (e.g., risk ratio or odds ratio) or inference

Answer 8

selection bias

Question 9

having two data peaks

Answer 9

bimodal

Question 10

a person or animal that harbors the infectious agent for a disease and can transmit it to others, but does not demonstrate signs of the disease

Answer 10

carrier

Question 11

an instance of a particular disease, injury, or other health conditions that meets selected criteria

Answer 11

case

Question 12

a set of uniformly applied criteria for determining whether a person should be identified as having a particular disease, injury, or other health condition

Answer 12

case definition

Question 13

the proportion of persons with a particular condition (e.g., patients) who die from that condition

Answer 13

case-fatality rate

Question 14

the first case or instance of a patient coming to the attention of health authorities

Answer 14

index case

Question 15

the case or instance of a patient responsible for transmitting infection to others; the instance of a patient who gives rise to an outbreak or epidemic

Answer 15

source case

Question 16

the enumeration of an entire population, usually including details on residence, age, sex, occupation, racial/ethnic group, marital status, birth history, and relationship to the head of household

Answer 16

census

Question 17

the progression of an infectious agent that leaves its reservoir or host through a portal of exit, is conveyed by a mode of transmission, and then enters through an appropriate portal of entry to infect a susceptible host

Answer 17

chain of infection

Question 18

the medical features (e.g., symptoms, medical examination findings, and laboratory results) that are used in a case definition

Answer 18

clinical criteria

Question 19

a disease that has been manifested by its symptoms and features

Answer 19

clinical disease

Question 20

an aggregation of cases of a disease, injury, or other health condition in a circumscribed area during a particular period without regard to whether the number of cases is more than expected

Answer 20

cluster

Question 21

a range of values for a measure (e.g., rate or odds ratio) constructed so that the range has a specified probability (often, but not necessarily, 95%) of including the true value of the measure

Answer 21

confidence interval

Question 22

the distortion of the association between an exposure and a health outcome by a third variable that is related to both

Answer 22

confounding

Question 23

exposure or transmission of an agent from a source to a susceptible host through touching (e.g., from a human host by kissing, sexual intercourse, or skin-to-skin contact) or from touching an infected animal or contaminated soil or vegetation

Answer 23

direct contact

Question 24

capable of being transmitted from one person to another by contact or close proximity

Answer 24

contagious

Question 25

a two-variable table of cross-tabulated data

Answer 25

contingency table

Question 26

the number of deaths attributed to a particular disease, injury, or other health condition during a specified period, divided by the number of new cases of that disease, injury, or condition identified during the same period

Answer 26

death to case ratio

Question 27

application of quantitative methods to decision-making

Answer 27

decision analysis

Question 28

personal characteristics of a person or group (e.g., age, sex, race/ethnicity, residence, and occupation)

Answer 28

demographic information

Question 29

any factor that brings about change in a health condition or in other defined characteristics

Answer 29

determinant

Question 30

association between an exposure and health outcome that varies in a consistently increasing or decreasing fashion as the amount of exposure increases

Answer 30

dose response

Question 31

the direct transmission of an infectious agent by means of the aerosols produced in sneezing, coughing, or talking that travel only a short distance before falling to the ground

Answer 31

droplet spread

Question 32

the constant presence of an agent or health condition within a given geographic area or population; can also refer to the usual prevalence of an agent or condition

Answer 32

endemic

Question 33

an extrinsic factor (e.g., geology, climate, insects, sanitation, or health services) that affects an agent and the opportunity for exposure

Answer 33

environmental factor

Question 34

the occurrence of more cases of disease, injury, or other health condition than expected in a given area or among a specific group of persons during a particular period

Answer 34

epidemic

Question 35

a histogram that displays the course of an outbreak or epidemic by plotting the number of cases according to time of onset

Answer 35

epidemic curve

Question 36

the traditional model of infectious disease causation having three components: an external agent, a susceptible host, and an environment that brings the host and agent together so that disease occurs

Answer 36

epidemiologic triad

Question 37

the study of the distribution and determinants of health conditions or events among populations and the application of that study to control health problems

Answer 37

epidemiology

Question 38

the aspect of epidemiology concerned with why and how a health problem occurs

Answer 38

analytic epidemiology

Question 39

the application or practice of epidemiology to control and prevent health problems

Answer 39

applied epidemiology

Question 40

the aspect of epidemiology concerned with organizing and summarizing data regarding the persons affected (e.g., the characteristics of those who became ill), time (e.g., when they become ill), and place (e.g., where they might have been exposed to the cause of illness)

Answer 40

descriptive epidemiology

Question 41

having come into contact with a cause of, or possessing a characteristic that is a determinant of, a particular health problem

Answer 41

exposure

Question 42

a negative test result for a person who actually has the condition similarly, a person who has the disease (perhaps mild or variant) but who does not fit the case definition, or a patient or outbreak not detected by a surveillance system

Answer 42

false-negative

Question 43

a positive test result for a person who actually does not have the condition. Similarly, a person who does not have the disease but who nonetheless fits the case definition, or a patient or outbreak erroneously identified by a surveillance system

Answer 43

false-positive

Question 44

an inanimate object that can be the vehicle for transmission of an infectious agent (e.g., bedding, towels, or surgical instruments)

Answer 44

fomite

Question 45

any of a variety of measures (e.g., mortality rate) that indicate the state of health of a given population

Answer 45

health indicator

Question 46

the observation that employed persons generally have lower mortality rates than the general population, because persons with severe, disabling disease (who have higher mortality rates) tend to be excluded from the workforce

Answer 46

healthy worker effect

Question 47

a group of persons whose risk for a particular disease, injury, or other health condition is greater than that of the rest of their community or population

Answer 47

high-risk group

Question 48

HIPAA

Answer 48

the Health Insurance Portability and Accountability Act, enacted in 1996, which addresses the privacy of a person’s medical information as well as postemployment insurance and other health-related concerns

Question 49

a person or other living organism that is susceptible to or harbors an infectious agent under natural conditions

Answer 49

host

Question 50

an intrinsic factor (e.g., age, race/ethnicity, sex, or behaviors) that influences a person's exposure, susceptibility, or response to an agent

Answer 50

host factor

Question 51

the constant presence at high incidence and prevalence of an agent or health condition within a given geographic area or population

Answer 51

hyperendemic

Question 52

resistance developed in response to an antigen (i.e., an infecting agent or vaccine), usually characterized by the presence of antibody produced by the host

Answer 52

active immunity

Question 53

the resistance to an infectious agent of an entire group or community (and, in particular, protection of susceptible persons) as a result of a substantial proportion of the population being immune to the agent

Answer 53

herd immunity

Question 54

immunity conferred by an antibody produced in another host This type of immunity can be acquired naturally by an infant from its mother or artificially by administration of an antibody-containing preparation (e.g., antiserum or immune globulin)

Answer 54

passive immunity

Question 55

a measure of the frequency with which new cases of illness, injury, or other health condition occurs among a population during a specified period

Answer 55

incidence

Question 56

the time interval from exposure to an infectious agent to the onset of symptoms of an infectious disease

Answer 56

incubation period

Question 57

invasion of the body tissues of a host by an infectious agent, whether or not it causes disease

Answer 57

infection

Question 58

the ability of an infectious agent to cause infection, measured as the proportion of persons exposed to an infectious agent who become infected

Answer 58

infectivity

Question 59

the separation of infected persons to prevent transmission to susceptible ones

Answer 59

isolation

Question 60

a type of epidemiologic database, organized similar to a spreadsheet with rows and columns in which information from cases or patients are listed each column represents a variable, and each row represents an individual case or patient

Answer 60

line listing

Question 61

a quantified relationship between exposure and a particular health problem (e.g., risk ratio, rate ratio, and odds ratio.)

Answer 61

measure of association

Question 62

the manner in which an agent is transmitted from its reservoir to a susceptible host (see also transmission)

Answer 62

mode of transmission

Question 63

any departure, subjective or objective, from a state of physiological or psychological health and well-being

Answer 63

morbidity

Question 64

a measure of the frequency of occurrence of death among a defined population during a specified time interval

Answer 64

mortality rate

Question 66

NHANES

Answer 66

The National Health and Nutrition Examination Survey, a representative survey of the civilian, noninstitutionalized US population conducted by the National Center for Health Statistics, designed to (1) estimate the proportion of the US population and designated groups with selected disease and risk factors; (2) monitor trends in selected behaviors, exposures, and diseases; and (3) study the associations among diet, nutrition, and health

Question 67

a distribution represented as a bell shape, symmetrical on both sides of the peak, which is simultaneously the mean, median, and mode, and with both tails extending to infinity

Answer 67

normal distribution

Question 68

a disease that, by law, must be reported to public health authorities upon diagnosis

Answer 68

notifiable disease

Question 69

a measure of association used in comparative studies, particularly case-control studies, that quantifies the association between an exposure and a health outcome; also called the cross-product ratio

Answer 69

odds ratio

Question 70

the occurrence of more cases of disease, injury, or other health condition than expected in a given area or among a specific group of persons during a specific period

Answer 70

outbreak

Question 71

an outbreak that results from persons being exposed to the same harmful influence (e.g., an infectious agent or toxin). The exposure period can be brief or can extend over days, weeks, or longer, with the exposure being either intermittent or continuous

Answer 71

common-source outbreak

Question 72

a common source outbreak in which the exposure period is relatively brief so that all cases occur within one incubation period

Answer 72

point-source outbreak

Question 73

an outbreak that spreads from person to person rather than from a common source

Answer 73

propagated outbreak

Question 74

an epidemic occurring over a widespread area (multiple countries or continents) and usually affecting a substantial proportion of the population

Answer 74

pandemic

Question 75

the ability of an agent to cause disease after infection, measured as the proportion of persons infected by an agent who then experience clinical disease.

Answer 75

pathogenicity

Question 76

a pathway into the host that gives an agent access to tissue that will allow it to multiply or act

Answer 76

portal of entry

Question 77

a pathway by which an agent can leave its host

Answer 77

portal of exit

Question 78

the proportion of cases identified by a test, reported by a surveillance system, or classified by a case definition that are true cases, calculated as the number of true-positives divided by the number of true-positives plus false-positives

Answer 78

predictive value positive

Question 79

the number or proportion of cases or events or attributes among a given population

Answer 79

prevalence

Question 80

a set of regulations based on the Health Insurance Portability and Accountability Act to protect the privacy of individually identifiable health information

Answer 80

privacy rule

Question 81

a general term for measures of association calculated from the data in a two-by-two table, including risk ratio, rate ratio, and odds ratio

Answer 81

relative risk

Question 82

the habitat in which an infectious agent normally lives, grows, and multiplies, which can include humans, animals, or the environment

Answer 82

reservoir

Question 83

the probability that an event will occur (e.g., that a person will be affected by, or die from, an illness, injury, or other health condition within a specified time or age span)

Answer 83

risk

Question 84

a sample of persons chosen in such a way that each one has the same (and known) probability of being selected

Answer 84

random sample

Question 85

a sample whose characteristics correspond to those of the original or reference population

Answer 85

representative sample

Question 86

change in physiologic status or in the occurrence of a disease, chronic condition, or type of injury that conforms to a regular seasonal pattern

Answer 86

seasonality

Question 87

the ability of a test, case definition, or surveillance system to identify true cases; the proportion of people with a health condition (or the proportion of outbreaks) that are identified by a screening test or case definition (or surveillance system)

Answer 87

sensitivity

Question 88

the ability or a test, case definition, or surveillance system to exclude persons without the health condition of interest; the proportion of persons without a health condition that are correctly identified as such by a screening test, case definition, or surveillance system

Answer 88

specificity

Question 89

the range of manifestations a disease process can take (e.g., from asymptomatic to mild clinical illness to severe illness and death)

Answer 89

spectrum of illness

Question 90

a study, usually observational, in which groups are compared to identify and quantify associations, test hypotheses, and identify causes. Two common types are cohort studies and case-control studies

Answer 90

analytic study

Question 91

an observational analytic study that enrolls one group of persons with a certain disease, chronic condition, or type of injury (case-patients) and a group of persons without the health problem (control subjects) and compares differences in exposures, behaviors, and other characteristics to identify and quantify associations, test hypotheses, and identify causes

Answer 91

case-control study

Question 92

an observational analytic study in which enrollment is based on status of exposure to a certain factor or membership in a certain group. Populations are followed, and disease, death, or other health-related outcomes are documented and compared

Answer 92

cohort study

Question 93

a study in which a sample of persons from a population are enrolled and their exposures and health outcomes are measured simultaneously; a survey

Answer 93

cross-sectional study

Question 94

an analytic study in which participants are enrolled before the health outcome of interest has occurred

Answer 94

prospective study

Question 95

an analytic study in which participants are enrolled after the health outcome of interest has occurred. Case-control studies

Answer 95

retrospective study

Question 96

without apparent symptoms

Answer 96

subclinical

Question 97

public health surveillance in which the health agency solicits reports

Answer 97

active surveillance

Question 98

monitoring of a person who might have been exposed to an infectious, chemical, radiologic, or other potentially causal agent, for the purpose of detecting early symptoms

Answer 98

medical surveillance

Question 99

public health surveillance in which data are sent to the health agency without prompting

Answer 99

passive surveillance

Question 100

a surveillance system that uses a prearranged sample of sources (e.g., physicians, hospitals, or clinics) who have agreed to report all cases of one or more notifiable diseases

Answer 100

sentinel surveillance

Question 101

the monitoring of the frequency of illnesses with a specified set of clinical features among a given population without regard to the specific diagnoses, if any, that are assigned to them by clinicians

Answer 101

syndromic surveillance

Question 102

a systematic canvassing of persons to collect information, often from a representative sample of the population

Answer 102

survey

Question 103

a combination of symptoms characteristic of a disease or health condition; sometimes refers to a health condition without a clear cause

Answer 103

syndrome

Question 104

any indication of disease noticed or felt by a patient

Answer 104

symptom

Question 105

transfer of an agent suspended in the air, considered a type of indirect transmission

Answer 105

airborne transmission

Question 106

indirect transmission by a vector in which the infectious agent undergoes biologic changes inside the vector as part of its life cycle before it is transmitted to the host

Answer 106

biologic transmission

Question 107

transmission of an agent by a living intermediary; indirect

Answer 107

vectorborne transmission

Question 108

transmission of an agent by an inanimate object; considered a type of indirect transmission; includes foodborne and waterborne transmission

Answer 108

vehicleborne transmission

Question 109

an experimental study that uses data from individual persons. The investigator specifies the type of exposure for each study participant and then follows each person's health status to determine the effects of the exposure

Answer 109

clinical trial

Question 110

an experimental study that uses data from communities. The investigator specifies the type of exposure for each community and then follows the communities' health status to determine the effects of the exposure

Answer 110

community trial

Question 111

a clinical trial in which persons are randomly assigned to exposure or treatment groups

Answer 111

randomized clinical trial

Question 112

the ability of an infectious agent to cause severe disease, measured as the proportion of persons with the disease who become severely ill or die

Answer 112

virulence

Question 113

a measure of the impact of premature death on a population, calculated as the sum of the differences between a predetermined minimally acceptable age (e.g., 65 years or current life expectancy) and the age at death for everyone who died earlier than that age

Answer 113

years of potential life lost (YPLL)

Question 114

an infectious disease that is transmissible from animals to humans

Answer 114

zoonosis

Question 169

NCHS

Answer 169

The National Center for Health Statistics, the US governmental organization responsible for national vital statistics and multiple national health surveys.