Scientific Method Flow Chart

Stylized flow chart

Sean Gladwell, Getty Images

 These are the steps of the scientific method in the form of a flow chart. You can download or print the flow chart for reference. This graphic is available for use as a PDF image.

The Scientific Method

This flow chart diagrams the steps of the scientific method.
This flow chart diagrams the steps of the scientific method. Anne Helmenstine

The scientific method is a system of exploring the world around us, asking and answering questions, and making predictions. Scientists use the scientific method because it is objective and based on evidence. A hypothesis is fundamental to the scientific method. A hypothesis can take the form of an explanation or a prediction. There are several ways to break down the steps of the scientific method, but it always involves forming a hypothesis, testing the hypothesis, and determining whether or not the hypothesis is correct.

Typical Steps of the Scientific Method

 Basically, the scientific method consists of these steps:

  1. Make observations.
  2. Propose a hypothesis.
  3. Design and conduct and experiment to test the hypothesis.
  4. Analyze the results of the experiment to form a conclusion.
  5. Determine whether or not the hypothesis is accepted or rejected.
  6. State the results.

If the hypothesis is rejected, this does not mean the experiment was a failure. In fact, if you proposed a null hypothesis (the easiest to test), rejecting the hypothesis may be sufficient to state the results. Sometimes, if the hypothesis is rejected, you reformulate the hypothesis or discard it and then go back to the experimentation stage.

Advantage of a Flow Chart

While it's easy to state the steps of the scientific method, a flow chart helps because it offers options at each point of the decision-making process. It tells you what to do next and makes it easier to visualize and plan an experiment.

Example of How to Use the Scientific Method Flow Chart

Following the flow chart:

The first step in following the scientific method is to make observations. Sometimes people omit this step from the scientific method, but everyone makes observations about a subject, even if it's informally. Ideally, you want to take notes of observations because this information may be used to help formulate a hypothesis.

Following the flow chart arrow, the next step is to construct a hypothesis. This is a prediction of what you think will happen if you change one thing. This "thing" that you change is called the independent variable. You measure what you think will change: the dependent variable. The hypothesis may be stated as an "if-then" statement. For example, "If the classroom lighting is changed to red, then student will do worse on tests." The color of the lighting (the variable you control) is the independent variable. The effect on student test grade is dependent on the lighting and is the dependent variable.

The next step is to design an experiment to test the hypothesis. Experimental design is important because a poorly designed experiment can lead a researcher to draw the wrong conclusions. To test whether red light worsens student test scores, you want to compare test scores from exams taken under normal lighting to those taken under red lighting. Ideally, the experiment would involve a large group of students, both taking the same test (such as two sections of a large class). Collect data from the experiment (the test scores) and determine whether the scores are higher, lower, or the same compared with the test under normal lighting (the results).

Following the flow chart, next you draw a conclusion. For example, if test scores were worse under the red light, then you accept the hypothesis and report the results. However, if the test scores under the red light were the same or higher than those taken under normal lighting, then you reject the hypothesis. From here, you follow the flow chart to construct a new hypothesis, which will be tested with an experiment.

If you learn the scientific method with a different number of steps, you can easily produce your own flow chart to describe the steps in the decision-making process!

Sources

  • American Society of Mechanical Engineers (1947). ASME Standard; Operation and Flow Process Charts. New York​.
  • Franklin, James (2009). What Science Knows: And How It Knows It. New York: Encounter Books. ISBN 978-1-59403-207-3.
  • Gilbreth, Frank Bunker; Gilbreth, Lillian Moller (1921). ​Process Charts. American Society of Mechanical Engineers.
  • Losee, John (1980). A Historical Introduction to the Philosophy of Science (2nd edition). Oxford University Press, Oxford.
  • Salmon, Wesley C. (1990). Four Decades of Scientific Explanation. University of Minnesota Press, Minneapolis, MN.