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Flashcards in Quick Review Deck (29)
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1

Key components of a research question are...

– the associations between 2 or more variables
– the associations between exposure and disease states
– the association between an independent and dependent
variables

2

What are the two main types of study designs?

Observational and experimental

3

What are the types of observational study designs?

Cohort, cross-sectional, case-control

4

What is the type of experimental design study?

RCT

5

What is a cross-sectional study

Observational study that involves data collection from a population, or a
representative subset, at one specific point in time

6

What is a cohort study

observational study that is longitudinal and involves data collection from a group of
people over many points to examine factors related to an outcome (e.g. disease)

7

What is a case control study

observational study in which two existing groups differing in outcome (e,g., disease)
are identified and compared on the basis of some supposed causal attribute (i.e.,
exposure)

8

What is RCT

Control and experimental, random sampling, discover if there is a relationship between an independent and dependent variable

9

What is a continuous variable

Take on potential values within a given range
Ex: Age, Scores on an a IQ tests (100, 90, 75, 140 etc…)
– Level of depression on a depression scale (27, 32, 61 etc)
– Height in inches (60, 50, 57 etc)
– Weight in pounds (98, 198, 298 etc)
– Standing after the short program in figure skating (1, 2, 3

10

What is a categorical variable

Can take on only one specific value based on
some agreed upon and clear system for assigning
the values
Ex: – Gender for the most part is assigned to each person
based on one value
• 1 female/ 0 male/ 2 transgender OR
• 0 female/ 1 male/ 2 transgender OR
• 0 transgender/ 1 female/ 2 male

11

What are the type of categorical variables

Ordinal, nominal

12

What is ordinal

There is a clear ordering of this variable, ordering matters
Ex: Gender:
• 0 male 1 female;
– the 0 and 1 do no indicate some rank or order
– Placement in Olympic ice hockey:
• Canada 1; USA 2; Russia 3;
– Here the numbers indicate a rank

13

What is nominal

Categorical scale, no intrinsic ordering

14

What are the types of scales we use to measure variables

ordinal, nominal, interval, ratio

15

What is an interval scale

There is no real 0 point in such scales; if there is
one it is arbitrary
Ex: IQ: 90, 100, 110
– The difference between 100 and 90 has the same meaning as between
100 and 110 but there is no real 0 (No 0 IQ; i.e. no IQ at all)
• Year of birth: 1992, 1997, 2002
– The difference between 1992 and 1997 is the same as 1997 and 2002 but
there in no real 0 (No 0 year; no year at all)
• Temperature: 50F, 55F, 60F
– The difference between 50 and 55 is the same as 55 and 60
Likert Scale

16

What is a ratio scale

Has absolute zeroes
Ex: Height
– Length
– Weight
– Time
– Temperature on Kelvin Scale
• 0 there is no molecular movement

17

What is p hat

p̂, sample proportion

18

What is mew

μ, mean of a population

19

What is sigma

σ = standard deviation of a population.

20

what is x bar

x̅, mean of a sample

21

what is N

Population size

22

what is y-intercept

b

23

What is degrees of freedom

df

24

what is frequency

f, fancy f

25

what is null hypothesis

Ho

26

What is alternative hypothesis

H1 or Ha

27

What is the slope of a line

m, tells how much ŷ increases or decreases for a one-unit increase in x

28

what is sample size

n

29

What is standard deviation of a sample

s