Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Epidemiology > Bias Sampling > Flashcards

Bias Sampling Flashcards

1
Q

what is internal validity affected by

A
  1. chance
  2. bias
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is chance

A

random error

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what is bias

A

any systematic error in an epidemiology study that results in an incorrect estimate of the association between exposure and risk of disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

true or false
there is an unpredictable over or underestimation of the measurement each time

A

false

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what are the 2 categories of bias

A

selection bias
information bias

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

which bias or error is based on who researchers select as study participants

A

selection bias

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what are types of selection bias

A

non-response bias
sampling bias
loss to follow-up bias

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what type of selection bias is used in prospective cohort studies

A

non-response vias

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what type of selection bias is used in case-control studies

A

sampling bias

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is one way sampling bias is avoided

A

randomization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what type of bias occurs when researchers are unable to collect accurate data on exposure or disease status

A

information bias

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

true or false:
information bias can be due to non-differential misclassification if both study groups are affected equally or differential misclassification if it affects one study group more than the other

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what are 2 types of information bias

A

interviewer bias
surveillance bias

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what can cause misclassification

A

recall bias
observer bias

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is the ability of respondents to accurately remember exposure of pet

A

recall bias

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is any kind of systematic discrepancy from the truth during the process of observing and recording information for a study

A

observer bias

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what is the target population

A

entire set of subjects whose characteristics are of interest to the research team

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what is a sample

A

subset of individuals in the target population from which researchers will draw their conclusions about the target population, following the process of statistical inference

19
Q

what is used to truly represent the population

A

method sampling

20
Q

which sampling has each member of the population a known probability of being selected

A

probability samples

21
Q

what are types of probability sampling methods

A

random sampling
systematic sampling
stratified sampling
cluster sampling

22
Q

what is the best method of sampling where each individual in the population has an equal chance of being selected

A

random samplingd

23
Q

which type of random sampling has each subject in a population has an equal chance of being selected

A

simple random sampling

24
Q

which type of random sampling has the selection a known and equal predefined interval such as select every 4th animal in a herd

A

systematic random sampling

25
Q

which type of random sampling occurs when the samples are divided into strata and random sample taken from each strata

A

stratified random sampling

26
Q

what type of random sampling is a probability sample in which each sampling unit is a collection of elements usually within a strata

A

cluster sampling

27
Q

which sampling techniques are often used in qualitative research where the aim is not to test a hypothesis but to develop an initial understanding of a population

A

non-probability sampling

28
Q

what is the purpose of non-probability sampling

A

produces biased population estimates as sampling is non-random

29
Q

true or false
nonrandom sampling is common in clinical research for practicality and leads to unbiased population estimates

A

false
it leads to biased population estimates

30
Q

what is qualitative research, to gain detailed knowledge about a specific phenomenon rather than make statistical interferences

A

purposive sampling

31
Q

how does purposive sampling work

A

the researcher chooses a sample most useful to the purposed of the research-must have clear criteria and rationale for inclusion

32
Q

what is a confounder

A

variable in a study that distorts the true relationship between an exposure and an outcome, so it seems that the exposure an the outcome are either more or less associated than they really are

33
Q

what does confounding usually occur

A

usually occurs when the 2 groups compared are not similar

34
Q

what is used in the design stage (before study is conducted)

A

randomisation
matching
restriction

35
Q

what is a part of the analysis stage

A

stratification
multivariate analysis

36
Q

what is the only way to equalize all confounders

A

randomisation (chance)

37
Q

what is sufficient sample size

A

randomization is likely to control both known and unknown confounders

38
Q

what is restriction

A

the study to a subgroup that is homogenous for particular characteristics such as age

39
Q

true or false
once data is collected, confounders must be known in order to control for them at this stage for the study

A

true

40
Q

what are two controllings for confounders

A

stratification
multivariate analysis

41
Q

what is the evaluate association within subgroups of the confounding variable

A

stratification

42
Q

what can be used to control the confounder

A

stratify the confounding variable by degree of urbanisation
calculation to determine the level of confounding by the confounding variable

43
Q

what is the technique that takes into account many variable at the same time that may confound the effect of exposure

A

multivariate analysis

Epidemiology (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions