Why Evaluate Scientific Information?

Do any of the following phrases sound familiar to you?

common phrases such as doctor recommended, proven to lower cholesterol, etc

Every day we are bombarded with messages like these, and others, that appear to be based on science. These messages are not just in print materials, such as the newspaper and magazines, but they are also on the Internet, television, radio, news reports, and journal articles.

How do you know what to believe? In order to evaluate text and other forms of media, use your science content knowledge, as well as knowledge about the nature of science and science process skills. You must be able to decide if a claim or statement is indeed scientifically based and if it is based on good science methodology and techniques.

According to Science Learning.org, understanding the nature of science and the way it is communicated can help you with the following:

  • Uncovering the purpose and meaning of media messages about science
  • Evaluating the science behind the messages
  • Identifying misrepresentations of science
  • Finding trustworthy sources of further information
  • Being critical consumers of science

It is not just in advertising that we see false scientific claims. It happens in scientific research as well. An article posted on the Alliance for Human Research Protection website, titled "Cancer Research False Claims," reported findings from the biopharmaceutical company AMGEN. According to the article, AMGEN’s head of research challenged the top 53 cancer research projects for cancer drug development. He wanted his team to duplicate and double-check the results before they began their work. “100 AMGEN scientists were astonished to find that they were able to replicate the results of only 6 of 53 widely cited landmark cancer research papers.” The article also stated that scientists from Bayer reported similar results. "Of 47 cancer projects at Bayer during 2011, less than one-quarter could reproduce previously reported findings, despite the efforts of three or four scientists working full time for up to a year."

In the May 2011 publication of Scientific American, there was an article titled "An Epidemic of False Claims: Competition and conflicts of interest distort too many medical findings." According to the article, "false positives and exaggerated results in peer-reviewed scientific studies have reached epidemic proportions in recent years.” The article states that the root of the problem is the public’s increasing expectations of science. "Being human, scientists are tempted to show that they know more than they do."

So, how do we evaluate or judge the reliability of what we hear and see?

Evaluating scientific explanations involves two steps.

Bias in Scientific Research

Look at these true and false statements from the U.S. Geological Survey. Decide if each statement is true or false, and then click on the appropriate button to submit your answer.


So, what is "good science?" Sound scientific investigations need to be designed and performed in a way that is objective and that is bias free. Two main types of bias are sampling bias and measurement bias.

 Click on each box to learn more about each type of bias.

Practice Identifying Bias

Now, let’s practice identifying sources of bias. The examples below are descriptions of studies conducted to collect data about the rate of teenage smoking. Read each study and the results, and then decide what type of bias is present, if any, in the experimental design. (Descriptions and feedback modified from USGS Data Exploration Unit).

How to Read Scientific Papers

Scientists communicate their research ideas, techniques, and results by publishing scientific papers in journals. Articles that summarize findings from many investigations are called secondary research articles or review articles. When a scientist conducts an investigation with original research and results to be published in a journal, the published work is considered a primary research article.

Primary research articles typically follow the same format and have six sections: abstract, introduction, materials and methods, results, discussion, and references. Sometimes the results and discussion section will be combined into one section. Each section of a primary research article has a specific purpose; knowing the parts of a primary research article can help you when you need to conduct research.

Click on the circles on the paper below to learn more about the information located in each part of primary research article. This information comes from the ScienceBuddies website.