This is a variable that is antecedent to the dependent variable; it is also called the experimental or treatment variable. The program or intervention is often an independent variable that is manipulated by the investigator.
Some independent variables are attributes that cannot be controlled by the investigator. Sometimes these are called assigned variables.
They are attributes such as gender, socio-economic class, cognitive level (IQ), and ethnicity. Some investigators will study the effects of certain attributes. For instance, investigators have studied the effect of gender on certain types of verbal tasks.
This is a variable that is consequence of or dependent on an antecedent variable (usually the independent variable). It is also called the outcome or effect variable. In general, this is the variable that is measured to determine the effect of an antecedent independent variable.