midterm 2 equations/calculations

Question 1

prevalence

Answer 1

cases / total population

Question 2

cumulative incidence

Answer 2

new cases in a specific period of time / # of people at risk at the beginning of the period

Question 3

incidence rate

Answer 3

of new cases during a given time / # of person time (years,months,days) contributed when people were at risk

Question 4

incidence rate can also be known as..

Answer 4

force of morbidity or mortality, incidence density

Question 5

point prevalance

Answer 5

the proportion of people in a population with the disease at a given point in time (ex July 8 2004)

Question 6

period prevalence

Answer 6

the proportion of individuals in a population with the disease at any time during a specified period (ex during 2004)

Question 7

use of prevalence

Answer 7

how many people are affected?
estimate probability an individual will have the disease during a point in time
project health care and other policy needs and issues
estimate costs associated with a particular disease

Question 8

prevalence cannot tell us..

Answer 8

how long someone has had the disease
cause of disease

Question 9

cumulative incidence should exclude… because..

Answer 9

people who already have the disease, people who cannot develop the disease
to avoid underestimating risk

Question 10

uses of cumulative incidence..

Answer 10

estimate probability (avg risk) that a person will develop the disease during a specific time period
research on causes, prevention, and treatment of a disease

Question 11

incidence rates shows us..

Answer 11

true rates - incidence rate can go up or down
denominator represents the window of time people were at risk at developing the disease, not the number of people at risk at the beginning
reported in unit of time (.. per 100 person days, … per 100 person years)

Question 12

use of incidence rates

Answer 12

research on causes, prevention, and treatment of disease

Question 13

crude mortality rates

Answer 13

of new deaths / average population during the year

Question 14

infant mortality rates

Answer 14

of deaths in children up to 1 year in a specific year / # of live births in the same year

Question 15

standardized incidence or mortality ratios

Answer 15

of deaths / # of expected standard population

Question 16

proportional mortality rate

Answer 16

proportion of deaths from a specific cause / proportion expected for standard population

Question 17

case fatality rate

Answer 17

of dead from disease in specific period / total number of cases

Question 18

how to establish causation

Answer 18

temporality - exposure must come first
strength of association - strong effect?
biological plausibility - what is the likely biological mechanism?
consistency - found across a range of studies?
dose response - level and duration of exposure

Question 19

sufficient cause

Answer 19

factor that will inevitably produce disease

Question 20

component cause

Answer 20

factor that contributes toward disease causation but not sufficient enough to cause disease on its own

Question 21

necessary cause

Answer 21

any agent that is required for the development of a given disease

Question 22

what is considered an exposure?

Answer 22

infectious agents
behaviours
intrinsic characteristics of individuals
social or environmental factors

Question 23

observational studies

Answer 23

the researcher does not intervene in any ways: measurement of occurrence of disease or health outcome, comparing patterns of expose and disease outcomes, identifying risk factors associated with heath/disease

Question 24

experimental studies

Answer 24

investigator tries to change something and measure the effect on the disease outcome - clinical trials, preventive trials

Question 25

descriptive studies

Answer 25

research that describes the occurrence of disease and/or exposure remember: PERSON PLACE TIME ask: WHO WHAT WHEN WHERE WHY

Question 26

analytic studies

Answer 26

primary purpose is to evaluate the association between the exposure or characteristic and the development of a particular disease WHY? HOW STRONG?

Question 27

ecological studies

Answer 27

compare the prevalence of exposures and disease occurrence in populations

Question 28

cross sectional studies

Answer 28

study group chosen to represent a subgroup of society/cross section of the population

Question 29

case control study

Answer 29

choose individuals with disease or outcome of interest and a comparison group without disease

Question 30

prospective cohort studies

Answer 30

follow up studies: follow people over time to see what happens compare rates of occurrence of disease in people with out without a particular exposure

Question 31

epidemiology (where is the word derived from? what does it mean)

Answer 31

epi - among demos - the people logia - study = the study of what is upon the people

Question 32

epidemiology dictionary definition

Answer 32

the study of the distribution and determinants of health-related states in specified populations, and the application of this study to control health problems

Question 33

applications of epidemiology

Answer 33

identifying the cause of a new syndrome assessing risk of exposure determine whether treatment “x” is effective identifying health service use needs and trends identifying practical prevention strategies

Question 34

endemic

Answer 34

cases are continually occurring in the population

Question 35

epidemic

Answer 35

outbreak of a disease in a localized group of people - spread by: vectors, carriers, sudden intro of a new pathogen; more cases than usually expected

Question 36

pandemic

Answer 36

epidemics that have spread beyond their local region and are affecting people in various/all parts of the world

Question 37

how many people fell ill from TB? (2016)

Answer 37

10.4 million people

Question 38

how many people died from TB? (2016)

Answer 38

1.8 million people including 400,000 with HIV and TB

Question 39

sensitivity

Answer 39

how well does the test classify people with disease as diseased? a/(a+c)

Question 40

specificity

Answer 40

how well does the test classify people without the disease as none diseased? d/(b+d)

Question 41

applications of epidemiology

Answer 41

identifying the cause of a new syndrome assessing risk of exposure determining whether treatment “x” is effective identifying health service needs and trends identifying practical preventions strategies

Question 42

ottawa health promotion strategies

Answer 42

build healthy public policy create supportive environments strengthen community action develop personal skills reorient health systems

Question 43

bradford hill criteria

Answer 43

temporality - exposure must come first strength of association - strong effect? biological plausibility - what is biological mechanism consistency - is it found across a range of studies dose response - level and duration of exposure