Module 2: 3 Research Designs

Question 0

Prognosis: P stands for

Answer 0

Population of interest

Question 1

Evaluate likelihood of outcomes developing over time in patients with a particular condition. “What is the chance of dying?” “What are the complications?”

Answer 1

Prognosis articles

Question 2

Prognosis: E stands for

Answer 2

Exposure/Prognostic factor

Question 3

Prognosis: O stands for

Answer 3

Outcome/Complication of interest

Question 4

Factors which are associated with causing a condition

Answer 4

Risk factor

Question 5

Factors which in people have the condition, influence the outcome

Answer 5

Prognostic factor

Question 6

Refers to its possible outcomes and the likelihood that each one will occur

Answer 6

Prognosis of a disease

Question 7

Is a patient characteristic that can predict that patient’s eventual outcome

Answer 7

Prognostic factor

Question 8

Examples of Prognostic factor

Answer 8

Comorbid, Demographic & Disease-specific “CDD”

Question 9

Age is an example of

Answer 9

Demographic

Question 10

Other conditions present like heart failure is an example of

Answer 10

Comorbid

Question 11

Tumor stage is an example of

Answer 11

Disease-specific

Question 12

Are the number of events that occur over time

Answer 12

Prognostic results

Question 13

Prognostic result is expressed in

Answer 13

Survival curves, Absolute terms & Relative terms “SAR”

Question 14

5 year survival rate is an example of

Answer 14

Absolute term

Question 15

Risk from prognostic factor is an example of

Answer 15

Relative terms

Question 16

Cumulative events over time is an example of

Answer 16

Survival curves

Question 17

Is a series of horizontal steps of declining magnitude. May represent true survival function for that population of a large enough sample was taken into account.

Answer 17

Plot of Kaplan-Meier estimate of the survival function

Question 18

Advantage of Kaplan-Meier: takes into account some types censored data, particularly _______, which occurs if a patient withdraws from a study.

Answer 18

Right-censoring

Question 19

Indicate losses, where a patient’s survival time has been right-censored.

Answer 19

Small vertical tick-marks

Question 20

Tries to establish if a particular exposure is responsible for causing an undesirable outcome.

Answer 20

Harm articles

Question 21

Harm: P stands for

Answer 21

Population might be at risk

Question 22

Harm: E stands for

Answer 22

Potentially harmful exposure

Question 23

Harm: O stands for

Answer 23

Outcome that these exposures might cause

Question 24

Study designs used in Prognosis & Harm

Answer 24

Cohort studies, Case control studies, Correlational designs & Case series

Question 25

Best design to use. Data are obtained from groups who have been exposed, or not exposed, to the new technology or factor of interest (ex: from databases) No allocation of _______ is made by the researcher. Best for studying the effect of predictive risk factors on an outcome.

Answer 25

Cohort. Exposure.

Question 26

Cohort advantages: ________ safe.

Answer 26

Ethically

Question 27

Cohort advantages: exposure may be linked to a

Answer 27

Hidden confounder

Question 28

Cohort advantages: ________ is difficult.

Answer 28

Blinding

Question 29

Cohort advantages: ________ not present.

Answer 29

Randomization

Question 30

Cohort advantages: for rare disease, large __________ or long follow-up necessary.

Answer 30

Sample sizes

Question 31

Patients with a certain outcome or disease and an appropriate group of controls without the outcome of disease are selected (usually with careful considerations of appropriate choice of controls, matching & etc) and the info is obtained on whether the subjects have been exposed to the factor under investigation.

Answer 31

Case-control

Question 32

Case-control advantages: _______ subjects needed than cross-sectional studies. _______ & _______.

Answer 32

Fewer. Quick & Cheap.

Question 33

Case-control advantages: only ________ method for very rare disorders or those with ________ between exposure and outcome.m

Answer 33

Feasible. Long lag.

Question 34

Case-control Disadvantages: reliance on ___________ to determine exposure status.

Answer 34

Recall/Records

Question 35

Case-control Disadvantages: Confounders. Selection of control groups is ________. Potential bias: _______ & ________.

Answer 35

Difficult. Recall & Selection.

Question 36

Systematic investigation of relationships among two or more variables, without necessarily determining cause and effect.

Answer 36

Correlational studies

Question 37

Indicate that an increase in one variable is associated with a decrease in the other variable.

Answer 37

Negative correlation

Question 38

Indicate that an increase in one variable is associated with a increase in the other variable.

Answer 38

Positive correlation

Question 39

Correlational advantages: _______ safe. ______ & _____.

Answer 39

Ethically. Cheap & Simple.

Question 40

Correlational Disadvantages: establishes ________ at most, not causality. _________ susceptibility.

Answer 40

Association. Recall bias.

Question 41

Correlational advantages: ________ may be unequally distributed. _____ bias. Group sizes may be _______.

Answer 41

Confounders. Neyman. Unequal.

Question 42

Lurking variables can change the association. (Refer on handout for example)

Answer 42

Simpson's paradox

Question 43

An incidence-prevalence bias. Arises when a gap in time occurs between exposure and selection of study participants. This bias crops up in studies of diseases that are quickly fatal, transient, or subclinical. Creates a case group not representative of cases in the community.

Answer 43

Neyman Bias

Question 44

Merely tracks patients or subjects with the same exposure. Limited to a number of patients only unlike cohort studies. ________ & _______ cases are discussed & presented.

Answer 44

Case series. Coherent & Consecutive.

Question 45

Case series advantage: for _____ & _____ diseases. Ethical. Cheap and simple.

Answer 45

Rare & new.

Question 46

Case series Disadvantage: ________ susceptibility. Confounders.

Answer 46

Selection bias