Concepts Journal Club 4

Question 1

Pilot

Answer 1

Preliminary small-scale study that researchers conduct in order to help them decide how best to conduct a large-scale research project.

Question 2

Contamination

Answer 2

Clearly-established problem with serious consequences in a biological laboratory.

Question 3

Responsivity (of effect measure)

Answer 3

How well a certain procedure or machine can detect something. E.g. a blood sample may have lots of HDL, but if the machine cannot detect it, you assume that there is not any HDL. Therefore, the responsivity of effect measure is low.

Question 4

Weak experimental design

Answer 4

A design with many flaws whose results have little to no validity. Randomized control trial is the strongest experimental design there is, the moment you miss out on control/randomization you have a weaker experimental design.

Question 5

Underspecified methods

Answer 5

Methods that are not really specified, so there is a part/procedure not fully mentioned or it is missing completely.

Question 6

Data dredging

Answer 6

When the researchers decides to perform a specific statistical analysis of the data after seeing the data already helping to portray the data in a specific way. This will result in authors getting a results which does not confirm their hypothesis so they look for other hypothesis to confirm their data.

Question 7

Omitting null results

Answer 7

Not mentioning results which did not correspons to the hypothesis.

Question 8

Selection bias

Answer 8

Selecting a sample based on traits/characteristics which the experimenters believe will help sway the results toward a specific favored outcome.

Question 9

Performance bias

Answer 9

Results from differences in the care provided to the participants other than the treatments being compared. It may occur if participants in a study are aware of which participants received which treatments.

Question 10

Detection bias

Answer 10

Related to the method of ‘blinding’ used in trials. It occurs when groups differ in the way outcome information is collected or the way outcomes are verified.

Question 11

Attrition bias

Answer 11

Occurs when subjects are lost in the trial (by dropping out of the study).

Question 12

Reporting bias

Answer 12

Selective revealing/suppresion of information. So it is bias caused by the experimenters decision to not include data which may affect the preferred outcome.

Question 13

Experimenter bias

Answer 13

Scientists performing the research influence the results, in order to portray a certain outcome. The experimenters influence the results.

Question 14

Confirmation bias

Answer 14

Tendency to search for, interpret, favor, and recall information in a way that confirms ones pre-existing beliefs/hypothesis. People display this bias when they gather or remember information selectively, or when they interpret it in a biased way.

Question 15

Transparency

Answer 15

Operating in such a way that it is easy for others to see what actions were performed. The ability to tell everything fully and truthfully for the greater good of science rather for personal gain.

Question 16

Control

Answer 16

Critical for internal validity, which allows you to establish a cause-and-effect relationship between variables.

Question 17

Causal role

Answer 17

One thing causes another. Causality is when a variable or measure is the true cause of the observable outcome as opposed to two unrelated things coincidentally displaying assocation.

Question 18

Two sample t-test

Answer 18

Also known as independent t-test, which is a method to test whether the unknown population means of two groups are equal or not.

Question 19

Chi-square test

Answer 19

Statistical hypothesis test that is valid to perform when the test statistic is chi-square distributed under the null hypothesis. It is used to determine whether there is a statistically significant difference between the expected frequencies and the observed frequencies in one or more categories of a contingency table. It can also be used to determine whether there is a relationshiop between two categorical variables.