Glossary
Dependent variable
This is the outcome variable that is being measured during the experiment that changes as a result of the independent variable. For example blood pressure could be the dependent (outcome) variable in response to the type of blood pressure treatment administered (independent variable, see below).
Impact Factor
An index assigned yearly to a scientific journal, often used to describe the journal’s importance or impact.
Independent variable
A variable that is manipulated or varied during the experiment. For example, the type of blood pressure treatment administered could be the independent variable, while blood pressure is the dependent (outcome) variable.
An outlier is a data point that differs significantly from the other data. It could be present due to variability in the data, or due to experimental error.
Outlier
Confounding variable
A variable that is related to both the independent and dependent variable, resulting in a spurious association.
Sampling bias
Sampling bias occurs when a sample is collected such that some members of the population are more likely to be selected than others (biasing the sample).
A control group is a standard that experimental groups or test groups are compared to in order to determine whether there is an effect. The control group does not receive any experimental intervention.
Control group
Significance refers to the level of confidence you have that a result is a real effect. P-value is the probability that the null hypothesis is true. The null hypothesis is the observed result is due to chance alone (and not a real effect).