Design

Question 0

Define: research hypothesis

Answer 0

Statement of researcher’s expectations about the relationship between variables under study.

Question 1

Define: operational definition

Answer 1

Definition of a variable based on how it will be used in a study; how a DV will be measured; how an IV will be manipulated.

Question 2

Define: null hypothesis

Answer 2

Statement of no difference or no relationship between variables; statistical hypothesis.

Question 3

Define: sample

Answer 3

Group of subjects in a study; part of the accessible population; intended to be representative of the whole population.

Question 4

Define: blinding

Answer 4

Techniques used to reduce experimental bias by keeping the subjects and/or investigators ignorant of group assignments and research hypotheses.

Question 5

Define: epidemiology

Answer 5

Study of distribution of disease in relation to person, place, and time; measures of risk associated with exposures to disease.

Question 6

Define: prevalence

Answer 6

Number of existing cases of a disease or condition at a given point in time, expressed as a proportion of the total population at risk.

Question 7

Define: incidence

Answer 7

The proportion of people who develop a given disease or condition within a specified time period.

Question 8

Process for addressing a research problem

Answer 8

Sort ideas, facts, theories (in clinical experience and profession literature). Start broad, then narrow down to one specific question.

Question 9

Primary vs Secondary source in literature

Answer 9

Primary: directly from author, best source of specific information
Secondary: description of 1 or more studies represented by someone other than author (review articles, textbook)

Question 10

Define: independent variable

Answer 10

Variable that is manipulated or controlled by researcher

Question 11

Define: dependent variable

Answer 11

Response variable that is assumed to be dependent on or caused by another variable (IV)

Question 12

Define: sampling bias

Answer 12

Bias that occurs when individuals who are selected for a sample overrepresent or underrepresent the underlying population characteristics

Question 13

Characteristics of a true experiment (3)

Answer 13

Manipulation of variables
Random assignment
Control group

Question 14

Design strategies: homogenous subjects

Answer 14

Subjects identical on a potentially confounding variable. (Limitation: results are only generalizable to specific type of people studied)

Question 15

Design strategies: blocking

Answer 15

Build extraneous variables into study design by using them as IVs. Example: block by age groups

Question 16

Design strategies: matching

Answer 16

Match subjects based on specific characteristics. Example: age-matched, sex-matched

Question 17

Design strategies: repeated measures

Answer 17

All levels of the IV experienced by all subjects. Subjects “matched” to themselves.

Question 18

Threats to validity (4)

Answer 18

Statistical conclusion validity
Internal validity
Construct validity
External validity

Question 19

Threats to statistical conclusion validity

Answer 19

Low statistical power (small sample size)
Assumption violated
Overall error
Poor reliability of measure

Question 20

Threats to internal validity

Answer 20

Changes in DV accounted for my other reasons:
History: other events occur between pre/post
Maturation: subjects grew spontaneous healing
Attrition: subject drop out
Testing effects: being tested influences result
Order effects: subject may learn from being tested
Instrumentation

Question 21

Threats to construct validity

Answer 21

The extent to which the operation represents a construct. (Does the pain scale reflect their pain? Does the stride consistency reflect stability?)

Question 22

Threats to external validity

Answer 22

Can the results be generalized to people, settings, times other than those in study?

Question 23

Define: retrospective research

Answer 23

Examination of data collected in the past

Question 24

Define: prospective research

Answer 24

Measurement collected in the present and the future

Question 25

Longitudinal research

Answer 25

Follow group over time
(+) document change in individuals
(-) long term commitments
(-) little flexibility
(-) threats to internal validity (maturation, history, learning effects)

Question 26

Cross-sectional research

Answer 26

Study a stratified group at a point in time and draw conclusions
(+) less costly and resource-intensive
(+) subjects tested only once
(-) potential selection bias
(-) cohort effects

Question 27

Vital statistics research

Answer 27

Birth rate: ratio of live births during a specific time period to total population at midpoint of time period

Mortality rate: ratio of deaths in specific period to population at midpoint of time period