Parts of The Scientific Method

This post will detail the specific parts of the scientific method. Our previous post titled: What is Research?  clearly specified that research was a systematic process. We also emphasized that scientific research (the way we do research) required precise procedures as a critical component of scientific research. We previously discussed what research was from a general perspective and used the example of an experimental design study. In this post, we explicitly examine components of the scientific method.

We’ve been using the example of an ABC drug study testing a new pain reliever for patients undergoing knee replacement surgery. Our example uses the research methodology called the experimental research design and incorporates the scientific method. The scientific method has a number of precise steps where each step is designed to ensure results of a research study are reliable and valid. The purpose of all scientific research studies  is to produce results and ultimately research knowledge across disciplines that are robust and trustworthy. [If you would like to see the post that details our example of the ABC Drug study click here]

What is Research
What is Research?

The scientific method  includes the following components…

  1. Observation
  2. Hypothesis/Prediction
  3. Experiment
  4. Measurement
  5. Conclusion


Observation: The initial step in the scientific method requires a thorough review of the topic of interest. In our ABC pain reliever study, our overall objective is to see if there is any evidence that the new ABC drug works as good as or better than the standard treatment. In the first step of the scientific method, we would need to gather and review all the information that already exists about our drug such as the current information about the ABC pain reliever and specific items such as measuring pain among patients.  This process is called a literature review. A precise and organized way of searching, gathering and summarizing what is already known about our area of interest (in a future post coming in a few weeks, we discuss the process of conducting a literature review in more detail).

Hypothesis and Prediction: Step two is the hypothesis. Think of the hypothesis as addressing a problem.The hypothesis is the idea to address the problem under consideration. The hypothesis is what the investigator thinks will happen and specifically states the best guess as to what the experiment or the research study will demonstrate once it is complete. The hypothesis must be declared BEFORE (known as ‘a priori’) the research process or experiment begins so the hypothesis prediction is not influenced by any events once the study is underway.

In summary, the hypothesis is the prediction and the experiment is the testing of that prediction.  In our drug example, the hypothesis would state that drug ABC works more effectively regarding pain relief after knee replacement surgery compared to the gold-standard treatment for pain relief among our knee replacement patient population.

Blood Sample Collection TubesExperiment and Measurement: The third and fourth steps in the scientific method are the experiment process itself and measurement of the outcomes that occurred during the experiment or data. The experiment tests the prediction by demonstrating very clearly how the hypothesis was tested. This is a crucial part of the scientific method and requires a lot of thought along with strict adherence to procedures in order to make sure the experiment is set up and conducted in a way that it  measures exactly what is required to test the hypothesis. Importantly in these steps of the scientific method, researchers must make sure that the experiment does not contain any factors that would ‘contaminate’ or confound results and introduce bias.

For example, in our ABC pain reliever study, we measure the patient’s pain symptoms and perception of their pain every hour after they wake up from their surgery. We observe and record our patient data and when our study is complete, we note that overall patient pain symptoms decreased and at a rate twice as fast as the gold-standard treatment.

Our discussion is purposely presented in an oversimplified manner to ensure the important pieces of information to take from steps 3 and 4 of the scientific method are very clear: i) understand what is being observed, ii) note how events or outcomes are measured and iii) ensure data is recorded and collected very carefully.

Conclusion: The final step in the scientific method is to provide a summary of the experiment and describe what occurred during the process.  When the study is finished, researchers conclude how the results of the experiment correspond with the original hypothesis (which was stated before the experiment started).

Classification of Research


Our discussion about research in our first few posts  has emphasized that research and analysis describe parts of a large systematic process that set out to find out what happens in a specific group under a predefined set of circumstances. We looked at how an experimental design approach used a systematic process, specifically the scientific method to test our predefined hypothesis.

The experimental design using the scientific method must ensure no outside factors (such as a second pain reducing medication in our ABC drug study) are actually responsible for the study’s results. In our study, if the design of the experiment did not clearly state intervals of time to measure patient pain symptoms or did not make sure patients were only taking one pain reducing medication at a time, our research results could be contaminated and other factors or variables could explain our final research results versus the performance of ABC drug itself. When this occurs, the research is said to contain confounding variables that may introduce bias into the overall results of the research.

By combining all the information in our posts to date, we continue becoming better critical consumers of research information thus, taking steps to make sure the research knowledge we have and use is valid and reliable. So far, we know that research is a systemic process and we must look for how the research information uses such processes. We also know it is necessary to have an overall understanding about what the current knowledge is about our research topic of interest and can expect the research information we use to have at the very least, a short summary of this information included.

Additionally, we understand it is important to examine how a study is being used as evidence in our topic of interest. We have an initial list of what the steps are in the scientific method so that we may examine research before us and ultimately know the research we choose to use followed a systematic process using specific scientific principles and thus is robust research information.

Next Post:  Influence and Bias in Research

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