Which best describes a variable in research?

A variable in research is fundamentally understood as a characteristic or attribute that can vary across individuals or observations. This variability is essential to research because it enables researchers to examine relationships, differences, or changes within a population. For example, variables can include age, income, education level, and attitudes, all of which can differ from person to person. By analyzing these variables, researchers can draw conclusions about trends, correlations, or causal relationships within the data.

The concept of variability distinguishes variables from constants, which remain unchanged throughout the research. Furthermore, while final results or outcome measurements are important aspects of conducting research, they are not themselves variables; rather, they depend on the data gathered from the variables. Lastly, theoretical considerations that lack practical application do not contribute to the empirical nature of research, making them separate from the concept of what defines a variable in this context.