Term

Definition
Upon, on top of
people or population
study of 


Term

Definition
The study of distribution and determinants of healthrelated states and events in specified populations, and the application of this study to control health problems 


Term
Assumptions in epidemiology 

Definition
disease and ill health are not randomly distributed
factors that determine this distribution are knowable and mostly modifiable
modification = prevention and control of disease 


Term

Definition
D  concerned with distribution of disease by persons, places, and times. Without a hypothesis  hypothesis generating
A  Concerned with identifying disease determinants. Hypothesis testing. Casual inference is ultimate goal. 


Term

Definition
Hypothesis (the link)
Description
Analysis 


Term

Definition
Describes changing patterns of community health problems
Provides clues
Health services planning
Public health policy 


Term

Definition
Upon, on top of people or population study of 


Term

Definition
prevent initial development of disease (risk factor reduction, immunization) 


Term

Definition
Early detection of existing disease to reduce morbidity (screening for cancer, high blood pressure, etc.) 


Term

Definition
Reduce the impact of acute worsening of disease 


Term
Epi Triad of infectious disease 

Definition
Host  Susceptible Agent  infectious or noninfectious Environment  promotes exposure Middle  vehicle
*or vector organism for indirect transmission 


Term
Triad of Noninfectious disease 

Definition
Host  genetics, stress, psychological factors Agent  behavior, diet, tobacco Environment  neighborhood, parks, food outlets 


Term
Modes of disease transmission 

Definition
1. escape of the agent from a source or reservoir 2. Conveyance 3. entry into host 


Term

Definition


Term

Definition
1. common vehicle a. single exposure (potato salad) b. multiple exposures c. continuous exposure (telephone receiver) 2. vector (organism) 


Term
Definition of "carrier" status 

Definition
A host "harbors" the infectious agent but appears not infected and there are no detectable signs or symptoms 


Term
effect of nonapparent infection on disease control and disease statistics 

Definition
when the proportion with nonapparent infection is high, statistics will underestimate rates of infection and overstate overall disease severity 


Term

Definition
habitual presence of a disease in a geographical area or population 


Term

Definition
occurrence of a disease in a geographical area that is unusually frequent 


Term

Definition


Term

Definition
the first disease case that appears in the population 


Term

Definition
the disease case that brings the group or population to the attention of public health personnel 


Term

Definition
time between infection and appearance of signs or symptoms 


Term

Definition
resistance of group or population to invasion and spread of infectious agent based on the immunity of a high proportion of the group 


Term

Definition
from a single brief and essentially simultaneous source of exposure
 all of the cases usually result in a single incubation period 


Term
propagated ("progressive") 

Definition
transmission from one individual to another
 epidemic extends over many incubation periods 


Term
general approach to outbreak investigation 

Definition
 verify the diagnosis  perform clinical studies  verify existence of epidemic  compare with past levels  person, place and time  calc. attack rates 


Term

Definition
new cases rapidly occuring in a welldefined population over a short period of time  total number of people at risk during that same period of time 


Term

Definition
*All times 100
new cases among contacts of initial cases occurring during a short period of time  (total number of people at risk during same period of time)  (initial cases) 


Term

Definition
1. a diseased state or symptom 2. the incidence of disease: the rate of sickness 


Term

Definition
a ratio where time is included in the denominator 


Term

Definition
special type of proportion that includes time  represents the probability of disease in a defined population  the basic measure of disease occurence 


Term

Definition
number of new cases of disease occurring during a defined period of time  number of people at risk for disease during defined period of time 


Term

Definition
all observed throughout a defined period of time  closed cohort  denominator = sum of all people at risk 


Term

Definition
all NOT observed for the full defined period of time  persontime units  denominator = sum of person observation time for each person at risk 


Term
cumulative incidence formula 

Definition
number of new cases of disease occurring during a defined period of time  initial population at risk of the disease 


Term
incidence density formula 

Definition
number of new cases of disease occurring during a defined period of time  persontime at risk for the disease 


Term
Incidence rate based on group level data 

Definition
number of new cases of disease occurring during a defined period of time  number of people in population at risk at the midpoint of the period 


Term

Definition
International Statistical Classification of Diseases and related health problems  used for coding and classifying mortality data from death certificates 


Term

Definition
International Statistical Classification of Diseases  Clinical Modification  Used to code and classify disease morbidity data from inpatient and outpatient records 


Term
problems determining who goes into the numerator 

Definition
1. what is the best case definition 2. detection (under or over diagnosis) 3. prevalent or incident (existing cases or new cases) 


Term
problems determining who goes into the denominator 

Definition
1. undercounting of certain population subgroups 2. not everyone in the denominator is at risk for disease 3. population studied may have limited external applicability 


Term
Limitations of hospital data 

Definition
1. admissions are selective 2. Hospital records are not designed for research 3. Populations at risk are not generally well defined 


Term

Definition
number of existing cases AT a point in time  number of people in the popualtion AT that point in time 


Term

Definition
Number of existing cases DURING a defined period of time  number of people in the population DURING that defined period of time 


Term
Relationship between incidence and prevalence 

Definition


Term

Definition
number of all new events during a period of time  number of people at risk for these events during same period 


Term
Problems with crude rates 

Definition
Crude rates can obscure the fact that subgroups in the population at risk exhibit significant differences in risk. Thus, rates may not be comparable across populations unless there is adjustment for populationspecific subgroup composition. 


Term
Why look at mortality quantitatively? 

Definition
 can indicate disease severity and determine if treatment has become more effective over time serve as a surrogate for incidence when the disease is severe  pinpoint difference in the risk of dying from a disease between population subgroups 


Term

Definition
number of people who die during a period of time  size of population during midpoint of the period 


Term
allcause annual mortality formula 

Definition
total number of people who die from any cause during 1 year  population at midpoint of that year 


Term
disease specific annual mortaity 

Definition
number of people who die of a specific disease during 1 year  population at risk at midpoint of that year 


Term

Definition
* proportion, so a %
number of people who die of a disease  number of people with the disease 


Term

Definition
*proportion, so a %
number of people who die of a disease  total deaths 


Term

Definition
1. age is associated with the disease or health state of interest 2. age distribution structure of the populations being compared are different 


Term
Direct method for ageadjustment 

Definition
compute the overall mortality rate that would be expected if each population had the same age structure as the standard population 


Term

Definition
 holds age constant  gives a more accurate picture of differences in rates across populations 


Term

Definition
 fictional rates are calculated  suppresses details of how subgroups differ across the variable used for adjustment 


Term

Definition
 used when age groupspecific rates are not available 


Term

Definition
probability of death vs probability of survival 


Term
Case fatality rate formula 

Definition
*rate, so a %
number of people who die of a disease  number of people with the disease 


Term

Definition
 good index of severity of a shortterm, acute disease  can measure benefit of a new therapy 


Term

Definition
percentage of people with a disease who are alive at the end of a specified time interval 


Term
5year survival rate formula 

Definition
*rate, so a %
number of cases of the disease who are alive 5 years later  number of cases of the disease 


Term
limitations of 5year survival rate 

Definition
 assumes the probability of surviving is equal throughout  does not use actual observed survival  cannot account for survival affect 


Term
creator of the first life table 

Definition


Term
limitations of classic life tables 

Definition
 assumes the probability of surviving is equal throughout the year or fixed interval 


Term
Numerators in KaplanMeier life tables 

Definition
 an event is instantaneous  numerator = the number of people who died at that instant  denominator = the number of people alive up to that instant, including those who died  minus withdrawals that occurred before that instant 


Term
KaplanMeier life table assumptions 

Definition
 no secular(temporal) changes in effectiveness of treatment or tendency toward survival over time  censoring must be independent of the probability of survival 


Term

Definition
the length of time that half of the study population survives 


Term

Definition
the sum of the individual survival times divided by the total number of people in the study population 


Term

Definition
observed survival in people with the disease  expected survival without the disease 


Term
cumulative incidence in an open cohort or closed cohort with incomplete followup 

Definition
number of cases of disease occurring during a defined period of time  initial population at risk of the disease 


Term

Definition
the probability of an event occurring  difficult to measure over time  applies to a population, not individuals  values range from 01, unitless  also expressed as a %  defined for a certain time period 


Term

Definition
 special form of proportion that includes a specification of time  probability of disease in a defined population over time  the basic measure of disease occurrence  a risk in disguise  the risk of acquiring a disease, and death from a disease is the best approx. by a measure of its incidence 


Term
Which measures of disease occurrence below gives you the most accurate information about risk? 

Definition


Term

Definition
Risk = (incidence rate * time) 


Term

Definition
Risk = 1  [exp ^(rate * time)] 


Term
Canons of Inductive Reasoning  Method of Difference 

Definition
examines differences among groups for clues as to why disease rates or other health problems vary across groups 


Term
Canons of Inductive Reasoning  Method of Agreement 

Definition
looks for commonality in groups that manifest the same health problem 


Term
Canons of Inductive Reasoning  Method of Concomitant Variation 

Definition
traces how exposure to a hazard varies in relation to disease or other health problem 


Term

Definition


Term

Definition

