Lecture 14 - General Methodological Concepts of Research

Question 1

What are the two types of research or study design?

Answer 1

• quantitative: numbers used to represent data

- qualitative: words used to represent data

Question 2

What are the two types of quantitative study designs?

Answer 2

• interventional: participants are forcibly allocated into study groups
• observational: participants are not forcibly allocated into study groups

Question 3

What is a population?

Answer 3

-all the individuals making up a common group

Question 4

What is a sample?

Answer 4

-subset of the population that is studied, ideally representative of the population

Question 5

What is a null hypothesis?

Answer 5

• a conservative hypothesis that states that there will be no difference between groups
• goal is typically to reject the hypothesis as it is the opposite of desired outcome

Question 6

What are the three stances a null hypothesis can take?

Answer 6

• superiority: “I’m not better”
• noninferiority: “I’m worse than”
• equivalency “I’m not equivalent”

Question 7

What is probability sampling?

Answer 7

-when every part of the population has a known probability of being in the sample

Question 8

What is simple random sampling?

Answer 8

Numbers are randomly assigned and subjects are either picked by random selection of numbers or by starting somewhere on the list and sequentially picking subjects

Question 9

What is systematic random sampling?

Answer 9

-numbers are randomly assigned then from a random point subjects are selected every Nth number from that point

Question 10

What is stratified simple random sampling?

Answer 10

-stratification of possible sample by desired characteristic followed by use of simple random sampling within strata

Question 11

What is stratified disproportionate random sampling?

Answer 11

-disproportionate use of stratified simple random sampling when strata are not at desired proportion with the population

Question 12

What is multi-stage random sampling?

Answer 12

-simple random sampling at multiple stages (ie. county, zip code, clinic, individual)

Question 13

What is cluster multi-stage random sampling?

Answer 13

-multi-stage random sampling where all elements at a stage are selected

Question 14

What is non-probability sampling?

Answer 14

• quasi-systematic sampling that is not truly random

- ie. selection of last names beginning with M-Z, individuals referenced by selected-peers

Question 15

What is the difference between patient-oriented outcome and disease-oriented outcomes?

Answer 15

Disease-oriented:

• gives insight into disease process that a patient will likely be unable to appreciate in a clinical setting
• ie. vitamin E is a good antioxidant

Patient-oriented:

• gives outcomes that are meaningful to patients and that they can understand
• ie. vitamin E does not prevent cancer or cardiovascular disease

Question 16

What is the difference between individual outcomes and combined outcomes?

Answer 16

Individual outcome:

• probability of a single outcome occurring
• ie. death

Combined outcome:

• probability at least one outcome from with in a possible group of outcomes
• ie. death, MI, target-vessel revascularization, or major bleeding

Question 17

What are the 4 key principles of bioethics?

Answer 17

Autonomy:

• must decide to participate without outside influence
• must have complete understanding of risks and benefits

Beneficence
-must do good for the patient, not just society

Justice
-equal and fair treatment for all

Nonmaleficence
-do no harm

Question 18

What is the difference between consent and assent?

Answer 18

Consent: agreement to participate of those legally and mentally capable

Assent: agreement to participate by those mentally capable but not legally capable (typically due to age)

Question 19

What is an institutional review board (IRB)?

Answer 19

• “ethics committee”
• reviews all human studies prior to the studies beginning
• goal is to protect the rights of the study subjects

Question 20

What is a data safety and monitoring board?

Answer 20

-monitors and reviews the study as it progresses looking for undue risk/benefit between groups