General Methodological Concepts of Research

Question 1

Name the 2 types of Quantitative Studies

Answer 1

Interventional and Observational

Question 2

Describe Interventional Study Design characteristics

Answer 2

aka. “experimental” have forced allocation study groups and have the potential to be less ethical

Question 3

Describe Observational Study Design characteristics

Answer 3

observe subject elements occurring naturally or elements that subjects choose to be a part of

there is no researcher-forced group allocation

Question 4

Describe the relationship observational studies have with proving causation

Answer 4

observational studies cannot prove causation

Question 5

List Interventional study designs in increasing level of evidence

Answer 5

phase 0, phase 1, phase 2, etc

Question 6

List Observational study designs in increasing level of evidence

Answer 6

Case reports

Ecological

Cross-sectional

case-control

cohort

Question 7

Define the null hypothesis in a study

Answer 7

a research perspective which states there will be no (true) difference between the groups being studied

researchers either reject or dont reject this perspective based on the results obtained via data analysis

Question 8

What are the 3 various statistical-perspectives that can be taken by the researcher for the null hypothesis?

Answer 8

Superiority

Noninferiority

Equivalency

Question 9

Explain the Superiority null hypothesis perspective. What is a common comparison it is used for?

Answer 9

the null hypothesis is “im not superior”

asks the question “I wonder if im better”

usually used when comparing to placebo

Question 10

Explain the Noninferiority null hypothesis perspective. What is a common comparison it is used for?

Answer 10

The null hypothesis is “im not worse”

asks the question “I wonder if im not worse”

Usually used to compare a new treatment to something that is already accepted to be effective

Question 11

Explain the Equivalency null hypothesis perspective. What is a common comparison it is used for?

Answer 11

The null hypothesis is “Im not equivalent”

asks the question “I wonder if im equivalent”

Question 12

True or False: Studies that yield a rejected null hypothesis of superiority are said to be less effective than what they were being compared to.

Answer 12

False

After a superiority null hypthesis is rejected, the relationship could still be either “noninferiority” and “equivalency”

Question 13

Compare probability and non probability samples

Answer 13

probability sample: every element in the population has a known probability of being included in the sample

Nonprobability sample: every element in the population does NOT have a known probability of being included in the sample

Question 14

In terms of probability sampling schemes, define Simple Random Sampling

Answer 14

assigning random numbers, then taking randomly selected numbers to acquire the desired sample size

(or assign random #’s and then take a sequential order of the randomly given numbers)

Question 15

In terms of probability sampling schemes, define Systematic Random sampling

Answer 15

assigning random numbers, sort these numbers, and then select subjects via a predetermined sampling interval (take every Nth numbers) to get the desired sample size

Question 16

In terms of probability sampling schemes, define multi-stage random sampling

Answer 16

uses simple random sampling at “multiple stages” towards patient selection

Ex. Take simple random samples out of one country, then out of one zip code, then out of one household, then out of one person

Question 17

In terms of probability sampling schemes, define clustered multi-stage random sampling

Answer 17

basically multi stage random sampling, however ALL elements at each stage are included in the study
Ex. ALL clinics in a zip code and then ALL households in a community

Question 18

In terms of probability sampling schemes, define Convenience (Quasi-systematic) sampling

Answer 18

aren’t really completely random. The researcher decides what fraction of the population is to be sampled and how they will be sampled.
Ex. All persons with last names C-D, all members that work for the same business, all MWF visitors of a clinic

Question 19

In terms of probability sampling schemes, define stratified random sampling

Answer 19

collecting subjects in different strata based on a desired characteristic (may be a known confounder) and then using simple random sampling to get the desired sample size

Question 20

In terms of probability sampling schemes, define stratified disproportionate random sampling

Answer 20

Collecting subjects in a stratified manner that helps achieve a desired proportional representation of a underrepresented portion of the population.

over sampling is an example of this, however over sampling requires a “weighted” return sample population back to the baseline population

Question 21

Describe the difference between patient-oriented outcomes and disease-oriented outcomes.

Answer 21

pt-oriented outcomes: avoiding a MI (things that most patients care about)

Disease-oriented outcomes: cholesterol number (most patients dont care about their cholesterol number if it isnt actively affecting them)

Question 22

Describe internal validity as it applies to methodology of study

Answer 22

methods inside of the study affect the internal validity of the study.

high internal validity means that the study is scientifically rigorous/standardized and the results are accurate/reproducible.

Question 23

True or False

3 of the 4 principles of bioethics must be met by a study in order to be ethical.

Answer 23

False

all 4 principles must be met

Question 24

List and describe the 4 principles of bioethics.

Answer 24

Autonomy: participants fully understand all of the risks/benefits that could occur in the study, and willingly volunteer for it

Beneficence: the researchers must have good reason to believe that the treatment will benefit the patient NOT society

Justice: equal and fair treatment of all patients must occur

Nonmaleficence: researchers must do no harm to subjects (no lying/witholding to subjects)

Question 25

List the purpose and 3 guiding principles of the Belmont Report

Answer 25

it’s purpose is to protect the human subjects involved in research

Respect for Persons: subjects must be autonomous and voluntarily involved

Beneficence: the risks of the research must be justified by the potential benefits of the treatment

Justice: risks and benefits of the research must be equally distributed to subjects

Question 26

Describe the difference between consent and assent

Answer 26

consent: mentally capable people over the legal consenting age (18) agree to be a subject after being completely informed

Assent: the same as above, except the subject is NOT able to give legal consent (too young and caregivers/guardians must give consent)

Question 27

What does IRB stand for, what is another name for them, and what do they do?

Answer 27

Institutional Review Board

Ethics committee

they protect human subjects from undue risk. Their decisions are regulated by law “they have teeth”

Question 28

What must the IRB do prior to a study beginning?

Answer 28

review all human subject studies

Question 29

What is the OHRP?

Answer 29

Office of Human Research Protections

an agency that administers and enforces regulations on research studies (basically enforces IRB decisions)

Question 30

List and describe the 3 levels of IRB reviews in terms of the risk to subjects, pt identifiers, and the amount of time it usually takes to be approved.

Answer 30

Full Board: used for all interventional trials with any risk to patients (takes the longest to be approved)

Expedited: minimal risk and/or no patient identifiers (middle ground in terms of approval time it requires)

Exempt: no pt. identifiers, low/no risk, and uses already gathered datasets. (gets approved very quickly)

Question 31

What is DSMB? when do they come into play?

Answer 31

Data Safety and Monitoring Board: semi-independent committee not involved int he conduct of the study

they review the study data at predetermined intervals “as the study progresses” to asses for undue risk/benefit between groups.

Question 32

Compare and contrast Systematic Review and Meta-analysis in terms of their location on the research evidence pyramid.

Answer 32

Systematic reviews: “collective book report” of several studies written up as one big study

Meta-Analysis: uses the data from several other studies and calculates figures as if they were all part of one big study

Both are at the same level, at the top of the pyramid (highest strength of evidence)

Question 33

Where are interventional (exploratory) and Pragmatic (explanatory) trials at on the research evidence pyramid?

Answer 33

they are at the same level, 2nd closest to the top.

Question 34

Define Equipoise

Answer 34

genuine confidence that an intervention may be worthwhile (risk vs. benefit) in order to use it in humans

Question 35

Give a pro and con perspective on the subject of equipoise

Answer 35

Pro perspective: this ensures that the subjects participation in the study will be worthwhile because they may gain the benefits of the experimental treatment

Con perspective: some believe placebo groups in a study to be unethical because the placebo group may not be receiving the benefits of the experimental treatment.

Question 36

What are study designs based on? (7 but really 6 things)

Answer 36

Perspective of the research question (hypothesis)

Group allocation / randomization

Ethics

Efficiency / practicality / cost

Internal validity

External validity / generalizability