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What Is a Controlled Variable in Science?

October 6, 2022

What Is a Controlled Variable in Science?

In order to make new discoveries about science, you must first learn how to set up an experiment. There are many ways to perform experiments and test theories, but some components of scientific discovery are always required.

A controlled variable is not of interest in the target of a study. A controlled variable would ideally hold no impact on the results and take away from a study. However, control variables have a large impact on the validity of a study’s findings. 

Controlled variables may seem difficult to navigate, but these variables can be controlled in many different ways.

What are Controlled Variables?

Before being able to address what is a controlled variable in science, you have to know what a control variable is. 

Control variable definition: Anything that is held constant or limited in a research study.

The scope of what constitutes a control variable is wide. A control variable can be anything you are not testing for that may impact the results of a study. Variables may be controlled directly by holding them constant throughout a study, or they may be controlled indirectly through methods like randomization or statistical control.

Identifying the necessary control variables from the beginning will make for a more complete and valid study. 

What Is a Controlled Variable in an Experiment?

Lack of awareness of control variables can lead to erroneous results. Control variables that are unaccounted for are often referred to as confounding variables and will impact the validity of your results. 

What is the controlled variable in an experiment? Here are some common examples: 

  • Temperature
  • Light
  • Age
  • Sample volume
  • Duration of experiment
  • Time of year

Experiments across various fields will address controlled variables differently. The most common control variables in biology will look very different from control variables in statistical studies. The field of study needs to be taken into account when determining control variables.

Most experiments have multiple control variables. In general, the broader the scope of the experiment, the more controlled variables there will need to be. Many controlled variables can be addressed in the location and design of the experiment from the beginning. 

Controlled variables should be kept consistent throughout all experimental groups. The impact of these variables should be minimized as much as possible. 

You want the results of your experiment to reflect the variables you chose to test for rather than being impacted by variables that you failed to control. The design of the experiment will have a large impact on the feasibility of controlling variables.

How Can You Use Controlled Variables in Science?

The best way to understand what controlled variables in science are first to understand how they are used.

When first designing a study, the controlled variables should be considered. Some experiments require much more control than others. The evaluation of controlled variables can indicate how feasible your experiment is going to be. 

Controlled variables are often found in studies outside of traditional scientific fields. The field of study will have an impact on the controlled variables you should consider. 

Control variables are used in studies from the following fields:

  • Biology
  • Medicine
  • Engineering
  • Statistics
  • Social Sciences
  • Business

Academic studies are often interdisciplinary. Professionals and students across all disciplines use scientific methods to study variables. Due to the variety of methods used to perform studies, there are many ways to control or account for variables.

author
Phina Pipia is a writer, educator, and performer. Her work can be found at phinapipia.com.

Phina Pipia