EBM Intro/Stats

Question 1

Systematic vs Random error

Answer 1

Bias/Bounding, errors in study design, unavoidable vs

Errors from measurements, biostat provides tools do deal with this

Question 2

Epidemiology

Answer 2

Study of distribution and determinants of health-related states or events and application of this study to control health related problems

Question 3

Clinical epidemiolgoy

Answer 3

Making predictions about individual patients by counting clinical events of groups of similar patients

Question 4

EBM

Answer 4

Using evidence from clinical epidemiology to treat patients

Question 5

Mantra

Answer 5

Chance, bias, confounding, if rule those out-truth

Question 6

why not look at individuals and look at what

Answer 6

They vary too much, instead look at probabilites of outcomes in similar patient groups

Question 7

excess mortality

Answer 7

people who died due to a procedure vs the control group

Question 8

System I vs System II

Answer 8

Jump to conclusions based on limited evidence, effortless

Takes effort, quantitiative analysis, when we have time to think

Question 9

Health

Answer 9

State of complete mental, physical, and social well being

Question 10

Health Outcomes

Answer 10

death, disease, discomfort, disability, dissatisfaction

Question 11

Epidemiological Transition

Answer 11

Acute, contagious diseases to chronic and noncontagious lifestyle diseases

Question 12

EBM decision

Answer 12

Current best evidence supports this way and is okay with patient and is congruent with clinical experience

Question 13

dyspnea

Answer 13

shortness of breath

Question 14

Prevalence vs Incidence vs incidence rate

Answer 14

Current cases expressed as proportion of total cases to total population-tells about past

New cases of disease over a finite time-risk of getting the disease

Risk of getting disease/time

Question 15

Rate vs Proportion vs Ratio

Answer 15

Ratio-numerator no included in denominator

Rate-Numerator and time included in denominator-incidence rate

Proportion-numerator included in denominator-prevelance rate

Question 16

Case definitions

Answer 16

diagnostic criteria for defining cases

Question 17

Disease prevalence (point/period prevalence)

Answer 17

What proportion of population has disease at specific point in time

Number of people with disease at given point in time/
Total number of people in population

Point is instantaneous and prevalance is over time

Question 18

Disease Incidence (cumulative incidence)

Answer 18

How quickly people are being diagnosed with disease *new cases

Cum incidence-proportion of a group that develops disease over a certain time=
number of new cases/
Number of people at risk of developing the disease over a defined time

Question 19

Incidence rate

Answer 19

Rate at which new disease has occurred in population at risk per some unit time

Number of new cases/
Total time experienced by the at risk population

Question 20

Incidence density

Answer 20

new cases/

incidence rate in dynamic changing population which people are under study and at risk for varying periods of time

Total time experienced b the at risk population
(same as incidence rate?-just population is dynamic)

Add up periods of observation
Number of cases/person years

Question 21

Point prevalence

Answer 21

start of study-proportion who had sickness

Question 22

Rate

Answer 22

TIME IN THE FUCKING DENOMINATOR

Question 23

Steady state

Answer 23

no variables are changing over time

Question 24

Prevalence

Answer 24

Incidence x Avg Duration

Question 25

Incidence

Answer 25

Prevalence/Duration

Question 26

Duration

Answer 26

Prevalence/Incidence

Question 27

Apparent incidence

Answer 27

Completely dependent on intensity of effort to identify cases

Question 28

Epidemic

Answer 28

increase in incidence in community or region

Question 29

Outbreak

Answer 29

small epidemic in limited locale

Question 30

Pandemic

Answer 30

Epidemic that crosses many international boundaries

Question 31

Endemic disease

Answer 31

constant presence of disease in particular area

Question 32

Case fatality rate

Answer 32

proportion of people who suffer from disease

Question 33

complication rate

Answer 33

proportion of people who suffer complication after trx

Question 34

infant mortality rate

Answer 34

number of death

Question 35

perinatal mortality rate

Answer 35

Number stillbirths and deaths in first week of life per 1000 births

Question 36

maternal mortality rate

Answer 36

Number maternal deaths related to childbirth/number of live births

Question 37

physician use of prevalence and incidence

Answer 37

Use prevalence to estmiate likelihood of diagnoses before test done -incidence is not better because it is comparison of groups vs 1 patient

Question 38

ways to express and compare risk

Answer 38

express- cumulive incidence and incidence rate | Compare-Measures of effect (abs risk difference and relative risk)

Question 39

Absolute risk/absolute risk difference

Answer 39

Abs risk=Incidence Absolute risk difference=Incidence of exposed- Incidence of unexposed ex. some has risk factor has increased risk of 3/1000 - easiest for patients to understand

Question 40

Relative Risk

Answer 40

I exposed/I unexposed AKA risk ratio aka crude mortality ratio How many times more likely are patients to get disease when exposed vs unexposed

Question 41

Random/Probability sample

Answer 41

Random-each person has equal probabilty of being sampled Probability-Each person has a known probability of being selected (not always equal) -allows weighing towards groups of interest/low freq

Question 42

Probabilty vs Odds

Answer 42

Probabilty:A/A+B Odds: A:B

Question 43

Addition/Mult rule

Answer 43

Addition=two independent events occurs (and) Mult=Probabilty of two mutually exclusive events occurs (or)

Question 44

Point Prevalence

Answer 44

Proportion of people in population who have disease at particular point in time %

Question 45

Period prevalane

Answer 45

Proportion of people who have diease over a specifd period of time %

Question 46

Cumulative incidence

Answer 46

proportion of population at risk that develops disease over a period of time %

Question 47

Incidence density

Answer 47

Rate of newcases per total amount of time people in a population where at risk - dynamic population (workers) - person time

Question 48

Incidence rate

Answer 48

rate at which new disease has occurred in the population at risk per some unit time