PH 150A Final Test With 100% Correct Solutions
epidemiology - ANSWER study of disease is distributed in populations and factors that
influence or determine this distribution
leading causes of death in US - ANSWER heart disease, cancer, stroke, respiratory
diseases
leading causes of death in males - ANSWER unintentional injury, heart disease, suicide,
cancer
leading causes of death in females - ANSWER cancer, unintentional injury, heart
disease, suicide
epidemiological principles of disease - ANSWER disease not randomly distributed;
follow predictable patterns; individuals have characteristics that protect it from
different diseases; characteristics may be genetics; diseases may have multiple causes
epidemiologic approach - ANSWER determine if exposure is associated with disease
outcome, if relationship is causal, and intervene to control exposure and prevent
disease outcome
epidemiology triad - ANSWER disease arises from interaction of host with an agent in
particular environment
Ignaz Semmelweis - ANSWER childbed fever; physicians and med students were
carrying infection from autopsy room to patients in First Clinic; policy designed: wash
hands before coming into contact with patients
Edward Jenner - ANSWER smallpox; created vaccine from cowpox
John Snow - ANSWER cholera; transmitted through contaminated water; went door to
door to collect information and was able to get water pump handle removed
natural history of disease - ANSWER development and course of disease in individual
over period of time
primary prevention - ANSWER educate individuals and communities to avoid exposure;
prevent initial development of disease; i.e. immunization
secondary prevention - ANSWER screen or survey populations to find early disease and
treat before it becomes established; i.e. screening for cancer
tertiary prevention - ANSWER treat established disease to avoid progression and
complications of disease; i.e. rehabilitation for stroke
direct transmission - ANSWER person to person contact
,indirect transmission - ANSWER common vehicle and vector
herd immunity - ANSWER resistance of group to an attack by an infectious disease to
which large proportion of group members are immune
incubation period - ANSWER interval from time of infection to time of onset of clinical
illness
induction period - ANSWER interval from time of disease initiation to diagnosis
endemic - ANSWER usual presence of disease within given geographic area
epidemic - ANSWER occurrence of disease of similar nature which is clearly in excess of
normal expectancy
pandemic - ANSWER refers to worldwide epidemic
morbidity - ANSWER those who are living with the disease
mortality - ANSWER those who died from disease
passive surveillance - ANSWER routine data used or physician or lab reports cases of
disease; inexpensive; not comprehensive
active surveillance - ANSWER project staff seek out cases of disease; expensive; more
comprehensive
sentinel surveillance - ANSWER intensive collection of case data from only part of
population; i.e. active surveillance at specific hospitals to track specified disease
attack rate - ANSWER number of people at risk in whom a certain illness develops / total
number of people at risk; useful for comparing risk of disease in groups with different
exposures; can be specific for give exposure
counts - ANSWER absolute number of occurences
proportions - ANSWER what fraction of population is affected? numerator always
included in denominator
rates - ANSWER how fast disease occurs in population; time included in denominator
ratio - ANSWER one number or rate relative to another; proportion is type of ratio, but
not all ratios are proportions
odds - ANSWER p / (1-p)
prevalence - ANSWER # of existing cases of disease / # persons in population;
proportion of population affected by disease at certain time
point prevalence - ANSWER # existing cases of disease / # persons in population at
instant
, period prevalence - ANSWER # existing cases of disease / # persons in population at
midpoint
cumulative incidence - ANSWER # new cases of disease (over X period) / # at-risk
population at beginning; if you develop disease but were not present at beginning of
study, then you are not in numerator or denominator
incidence density - ANSWER # new cases of disease / person-time from at-risk
population
relationship between incidence and prevalence - ANSWER prevalence equals about
incidence times duration
decrease in prevalence - ANSWER decrease in incidence; rapid cures or deaths
increase in prevalence - ANSWER increase in incidence; long-term disease with slow
death or cure rates
death rate - ANSWER number of deaths in defined population in specified period of time
case-fatality rate - ANSWER number of deaths among persons with particular disease; #
of persons with disease A who die / total # of person with disease A per year x 100 (or
1000) cases
cause-specific death rate - ANSWER # deaths from cause A / midyear population per
year x 1000 population
problems with cumulative incidence - ANSWER denominator can be imprecise: assumes
entire population was at risk for entire observation time (unlikely because of loss to
follow-up, etc.); underestimates risk
proportionate mortality - ANSWER # deaths from cause A / all deaths per year x 1000
deaths
relationship between incidence and mortality - ANSWER mortality good reflection of
epidemiology - ANSWER study of disease is distributed in populations and factors that
influence or determine this distribution
leading causes of death in US - ANSWER heart disease, cancer, stroke, respiratory
diseases
leading causes of death in males - ANSWER unintentional injury, heart disease, suicide,
cancer
leading causes of death in females - ANSWER cancer, unintentional injury, heart
disease, suicide
epidemiological principles of disease - ANSWER disease not randomly distributed;
follow predictable patterns; individuals have characteristics that protect it from
different diseases; characteristics may be genetics; diseases may have multiple causes
epidemiologic approach - ANSWER determine if exposure is associated with disease
outcome, if relationship is causal, and intervene to control exposure and prevent
disease outcome
epidemiology triad - ANSWER disease arises from interaction of host with an agent in
particular environment
Ignaz Semmelweis - ANSWER childbed fever; physicians and med students were
carrying infection from autopsy room to patients in First Clinic; policy designed: wash
hands before coming into contact with patients
Edward Jenner - ANSWER smallpox; created vaccine from cowpox
John Snow - ANSWER cholera; transmitted through contaminated water; went door to
door to collect information and was able to get water pump handle removed
natural history of disease - ANSWER development and course of disease in individual
over period of time
primary prevention - ANSWER educate individuals and communities to avoid exposure;
prevent initial development of disease; i.e. immunization
secondary prevention - ANSWER screen or survey populations to find early disease and
treat before it becomes established; i.e. screening for cancer
tertiary prevention - ANSWER treat established disease to avoid progression and
complications of disease; i.e. rehabilitation for stroke
direct transmission - ANSWER person to person contact
,indirect transmission - ANSWER common vehicle and vector
herd immunity - ANSWER resistance of group to an attack by an infectious disease to
which large proportion of group members are immune
incubation period - ANSWER interval from time of infection to time of onset of clinical
illness
induction period - ANSWER interval from time of disease initiation to diagnosis
endemic - ANSWER usual presence of disease within given geographic area
epidemic - ANSWER occurrence of disease of similar nature which is clearly in excess of
normal expectancy
pandemic - ANSWER refers to worldwide epidemic
morbidity - ANSWER those who are living with the disease
mortality - ANSWER those who died from disease
passive surveillance - ANSWER routine data used or physician or lab reports cases of
disease; inexpensive; not comprehensive
active surveillance - ANSWER project staff seek out cases of disease; expensive; more
comprehensive
sentinel surveillance - ANSWER intensive collection of case data from only part of
population; i.e. active surveillance at specific hospitals to track specified disease
attack rate - ANSWER number of people at risk in whom a certain illness develops / total
number of people at risk; useful for comparing risk of disease in groups with different
exposures; can be specific for give exposure
counts - ANSWER absolute number of occurences
proportions - ANSWER what fraction of population is affected? numerator always
included in denominator
rates - ANSWER how fast disease occurs in population; time included in denominator
ratio - ANSWER one number or rate relative to another; proportion is type of ratio, but
not all ratios are proportions
odds - ANSWER p / (1-p)
prevalence - ANSWER # of existing cases of disease / # persons in population;
proportion of population affected by disease at certain time
point prevalence - ANSWER # existing cases of disease / # persons in population at
instant
, period prevalence - ANSWER # existing cases of disease / # persons in population at
midpoint
cumulative incidence - ANSWER # new cases of disease (over X period) / # at-risk
population at beginning; if you develop disease but were not present at beginning of
study, then you are not in numerator or denominator
incidence density - ANSWER # new cases of disease / person-time from at-risk
population
relationship between incidence and prevalence - ANSWER prevalence equals about
incidence times duration
decrease in prevalence - ANSWER decrease in incidence; rapid cures or deaths
increase in prevalence - ANSWER increase in incidence; long-term disease with slow
death or cure rates
death rate - ANSWER number of deaths in defined population in specified period of time
case-fatality rate - ANSWER number of deaths among persons with particular disease; #
of persons with disease A who die / total # of person with disease A per year x 100 (or
1000) cases
cause-specific death rate - ANSWER # deaths from cause A / midyear population per
year x 1000 population
problems with cumulative incidence - ANSWER denominator can be imprecise: assumes
entire population was at risk for entire observation time (unlikely because of loss to
follow-up, etc.); underestimates risk
proportionate mortality - ANSWER # deaths from cause A / all deaths per year x 1000
deaths
relationship between incidence and mortality - ANSWER mortality good reflection of
