Epi 1 Part 2

Front 1

Prevalence

Back 1

The Proportion (%) of a specific population or sample with a given Disease, risk factor injury...

Front 2

Prevalence used in:

Back 2

Cross-sectional

Cohort

Case control

RCT

Front 3

Incidence Rate

Back 3

-Incidence refers to the occurrence of a health outcome

- incidence is always measured in a reference to a given unit of time, as rate

- IR = the number of new cases of a health outcome over a specific. Of time

Front 4

IR used in

Back 4

Can ONLY be derived from a Cohort study design

Front 5

Sats that measure the frequency of a health outcome

Back 5

Prevalence

Incidence Rate

Front 6

Stats that measure the association between risk factors and outcome

Back 6

Correlation (R)

Relative Risk (RR)

Odds Ratio (OR)

Attributable Risk (PAR)

Front 7

Correlation

Back 7

Measures the Strength and Direction of the association between the health outcome and an exposure (risk factor )

Front 8

Correlation found in

Back 8

Any research design can produce correlation data

Front 9

Relative risk

Back 9

How the incidence rate of the health outcome changes according to the level of the risk factor (high, medium, low physical activity)

Front 10

Relative Risk found from

Back 10

Only from a Cohort study design (just like the Incidence rate)

Front 11

Odds Ratio

Back 11

How the prevalence of the risk factor differs among those with (cases) or without (controls) the health outcome

Front 12

Odds Ratio found from

Back 12

Derived from a case-control study design (usually retrospective)

"Those with lung cancer have a greater odds of having smoked"

Front 13

Attributable risk

Back 13

Evaluates how much (%) risk for the health outcome within the sample can be attributed to a given risk factor

Compares the relative risks associated with different risk factors

Used to evaluate the relative impact of one risk factor over another

Front 14

Equation for prevalence

Back 14

Number of people with the health-related outcome at a specific time

Divided by

Total number of people in the population at risk at this specific time

Usually expressed as a percentage

Front 15

Equation for incidence rate

Back 15

Number of people who developed the health related outcome in a specific period of time (# of new cases)

Divided by

some of the periods of time for a which each person in the population is at risk (# of person years)

#of cases/ # of person years

Front 16

Relative Risk equation

Back 16

IR of comparison group

Divided by

IR of the reference group

Front 17

The RR value of the reference group

Back 17

Always 1.0

💯

Front 18

Non directional

Back 18

Keep the numbers the same

"As likely" compared to reference group

Front 19

Directional

Back 19

Take the difference between the reference group and the comparison group.

"More or less likely"

Front 20

Clinical vs. population attributable risk

Back 20

CAR

Estimates how many cases in the sample of the study population with the given risk factor would be eliminated if the risk factor we're eliminated

I.e. the % of CHD deaths in the sedentary group that wouldn't occur if all the individuals in the sedentary group became active.

Front 21

Population attributable Risk

Back 21

PAR

Estimates how many cases in the whole study population would be eliminated if the risk factor we're eliminated.

I.e. the % of all CHD deaths in the study population that wouldn't occur if all the individuals in the sedentary group became active.

Front 22

95% CI

Back 22

Provides the RANGE of values within which we can be 95% sure the values are true.

If the study we're repeated 100 times, it would only be off 5 times.

Wide range= less precise outcome

Narrow Range= more precise outcome

Front 23

P value- probability value

Back 23

Determines the likelihood that the results of a study are a fluke and occurred simply due to chance.

Front 24

Good P-value

Back 24

A P-value of 0.05 indicates that the result of the study would occur simply by chance 5% of the time.

Front 25

Validity

Back 25

A measurement of how true the outcomes (results/conclusions) of a study are

Front 26

Confounding

Back 26

Occurrs when a variable other than the risk factor (IV) is associated with both the DV and the IV (risk factor) of interest.

Front 27

How to control confounding variables

Back 27

Measure them then adjust for them (fancy math)