Common Statistical Tests

Question 1

statistics that summarizes characteristics of a dataset

Answer 1

descriptive statistics

Question 2

statistics that allows you to test a hypothesis

Answer 2

inferential statistics

Question 3

study that provides details about who, when, where in relation to what (outcome)

Answer 3

descriptive studies

Question 4

study that answers why or how; test the hypothesis

Answer 4

analytic study

Question 5

detailed report of individual patient; typically a novel or unusual case ex. Phineas Gage

Answer 5

case report

Question 6

detailed report on several individual patients; no comparison group; retro or prospective

Answer 6

case series

Question 7

study that looks at data at a single point in time

Answer 7

cross-sectional study

Question 8

study that has unit of measure being a group, not separate individuals; used to understand relationships b/t outcome and exposures at population level

Answer 8

ecological studies

Question 9

assuming what is true of a population is true for the individual members of that population

Answer 9

ecological fallacy

Question 10

researcher observes effect of a specific variable

Answer 10

observational study

Question 11

researcher manipulates conditions and observes effects in controlled setting

Answer 11

experimental study

Question 12

compare group w/ defined exposure/risk factor to group without exposure; risk factor must be present before disease development

Answer 12

cohort study

Question 13

ex. individuals who use tanning beds have higher risk of developing skin cancer than those who do not

Answer 13

cohort study

Question 14

compares group of people w/ disease to group without that disease; retrospective

Answer 14

case-control study

Question 15

ex. individuals w/ skin cancer had higher odds of indoor tanning in the past than those without skin cancer

Answer 15

case-control study

Question 16

statistical analysis that combines results of multiple scientific studies

Answer 16

meta-analysis study

Question 17

this specific trial is prospective and measures effectiveness of a new intervention or treatment

Answer 17

randomized controlled trials (RCTs)

Question 18

trial that compares effect of a series of greater or equal to 2 treatments on a subject; subject serves as their own control

Answer 18

crossover clinical trials

Question 19

selecting group from whom you will actually collect data in your research

Answer 19

sampling

Question 20

type of sampling that is randomization of a simple frame using random number generation

Answer 20

simple

Question 21

type of sampling that divides a population into groups w/ similar characteristics; then takes random samples from each group

Answer 21

stratified

Question 22

similar to stratified, except groups are representative of population; not always accurate

Answer 22

cluster

Question 23

sample every nth person or group

Answer 23

systematic

Question 24

participants in the control and experimental groups are paired up

Answer 24

matched sampling

Question 25

characteristics required for participants to be included

Answer 25

inclusion criteria

Question 26

prevents selection bias in the RCTs by concealing the allocation of participants into groups until the moment of assignment (think match day)

Answer 26

concealed allocation

Question 27

occurs when some members of pop. are systematically more likely to be selected in a sample than other members

Answer 27

selection bias

Question 28

when participants leave/withdraw during a study

Answer 28

attrition

Question 29

bias introduced if characteristics of people lost to follow up differ from those who remain in the study

Answer 29

attrition bias

Question 30

systematic error when participants do not remember previous events/experiences accurately or omit details

Answer 30

recall bias

Question 31

bias that deals with error in data collection

Answer 31

measurement bias

Question 32

participants change behavior b/c they are aware they are being observed

Answer 32

Hawthorne Effect

Question 33

subjects in diff. groups are not treated the same

Answer 33

procedure bias

Question 34

a distortion that modifies an association b/t an exposure and an outcome b/c a factor is independently associated w/ the exposure and outcome (ex. ice cream sales and shark attacks)

Answer 34

confounding bias

Question 35

variable experimenter manipulates

Answer 35

independent variable

Question 36

what is affected by independent variable

Answer 36

dependent variable

Question 37

variable that deals with 2 or more groups being measured

Answer 37

categorical

Question 38

type of categorical variable that deals with descriptive only and no order

Answer 38

nominal

Question 39

type of categorical variable that deals with the sequence of categories being ordered so we can assign numbers

Answer 39

ordinal

Question 40

variable that can be quantified as a number

Answer 40

numerical

Question 41

any number is possible b/t 2 integers

Answer 41

continuous

Question 42

represent measured quantities of things, allowing for degree of difference b/t two values

Answer 42

interval

Question 43

whole integers; only some numbers possible

Answer 43

discrete

Question 44

explores 1 variable in a set at a time

Answer 44

univariate analysis

Question 45

explores 2 variables in a set at a time

Answer 45

bivariate analysis

Question 46

explores multiple variables in a set at a time; reduces chance of bias

Answer 46

multivariate analysis

Question 47

how much variability exists in a set of values, around the mean of these values

Answer 47

standard deviation

Question 48

these both decrease as sample size increases

Answer 48

standard deviation and standard error

Question 49

estimate of how much variability exists in a (theoretical) set of a sample means around the true population mean

Answer 49

standard error

Question 50

measure of the spread of a dataset

Answer 50

variability

Question 51

diff. b/t highest and lowest value

Answer 51

range

Question 52

range of the middle half of a distribution

Answer 52

interquartile range

Question 53

average distance from the mean

Answer 53

standard deviation

Question 54

average of squared distances from the mean

Answer 54

variance

Question 55

concept of how the data evens out

Answer 55

regression to the mean

Question 56

shows data near the mean occur more frequently than data far from mean; probability distribution that is symmetric about the mean

Answer 56

normal distribution

Question 57

mean of 1 and a standard deviation of 1

Answer 57

standard normal distribution

Question 58

extreme values at right end

Answer 58

positive skew

Question 59

extreme values at left end

Answer 59

negative skew

Question 60

occurrence of new cases

Answer 60

incidence

Question 61

number of existing cases

Answer 61

prevalence