How does science work?

Science is an iterative process. What we know today may change based on what we learn tomorrow.

Why do scientists change their minds? Why has the CDC made one statement regarding mask recommendations and then changed it? Why was the initial goal to flatten the curve and now the goal is elimination of the virus? How do I know what is real when the goal keeps changing?

Scientists are trained in specific disciplines to ask questions, conduct research, write, and teach. They generally have expertise in their specific field well beyond the average person. They often know something that no-one else knows because of research they have done. At the same time, research takes time for consensus. Researchers often debate with each other for a long time to arrive at a consensus. This discourse is part of the scientific process, which is designed to be self-correcting in the pursuit of truth. At one time, scientists thought that life was encoded by proteins instead of by DNA . Preformationism (growth of preformed parts results in offspring) was eventually replaced with epigenesis (offspring grow from undifferentiated parts). Prior to the cholera epidemic of 1854 and the work of John Snow, people did not understand that cholera was transmitted via infected water. A more recent example is the addition of domains to classify life when the highest classification before was kingdom.

Scientists conduct experiments to test their hypothesis and over time a consensus is determined. As new information is uncovered, the consensus may be challenged.

Scientists are also human. Sometimes they make mistakes. As for any human, it is always easier to see mistakes in someone else than in self. In a normal science cycle, the disagreements, anomalies, and data are battled out at conferences, in lab meetings, at department presentations, and in the peer-review process. COVID-19 hit the world so fast that news articles became the primary source of information instead of peer-reviewed scientific literature, even for scientists. News articles were followed by preprints which were then followed eventually by peer-reviewed articles. Sufficient time did not exist for the normal process of review, analysis, and replication before agreement to happen before data became public. Scientists do not always see eye-to-eye, especially for new and emerging areas of research. This fact has become increasingly obvious during the COVID-19 pandemic as many experts and news sources have tried to explain the pandemic to the United States.

Scientists are also prone to bias based on personal convictions, political affiliations, geographic location, personal experience, etc. just like every other person on this planet. They may have a broader and deeper knowledge base of specific topics than the general public, but they are not completely neutral sources of information. A current example during COVID-19 is the John Snow Memo versus the Great Barrington Declaration. Both items contain statements which can be argued. The Great Barrington Declaration does not explain how to properly shield the vulnerable, nor does it include anomalies such as re-infection. The John Snow Memo states that it is not ethical to lockdown large swaths of the population for an extended period of time but does not explain how additional prolonged lockdowns of the general population are more ethical than protecting a portion of the population. They also do not address the number of potential COVID-19 deaths in the context of the number of predicted deaths due to starvation resulting from the fallout of tanking economies. provides a platform for scientists to share their knowledge related to news articles and well-shared research articles. Evidence is weighted based on the following chart:

The purpose of annotations is to provide context into the data in news articles/etc. based on expertise of doctors, Ph.Ds and graduate students. The tags of Well Supported, Needs More Context, or Poorly Supported are judgements made by the annotator on the validity of a factual claim or assumption given a broader scientific context. The tag is not intended to comment on the personal or political viewpoint of an author, but rather to address the quality of evidence supporting a given statement. The aim of is to provide relevant additional information on the latest news regarding COVID-19 so that readers can make informed decisions based on the best science.

Be humble. . . . . Stay curious!

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Viral Feedback

Providing scientific perspectives on public information regarding COVID-19.

Viral Feedback

A community of scientists, health professionals, and associated content experts providing data driven analysis, in the form of annotations, of SARS-CoV-2 and COVID-19-related news reports, government actions, breaking scientific papers, and other media.

Michelle Gerst, Ph.D.

Written by

Senior Moderator for Viral Feedback

Viral Feedback

A community of scientists, health professionals, and associated content experts providing data driven analysis, in the form of annotations, of SARS-CoV-2 and COVID-19-related news reports, government actions, breaking scientific papers, and other media.

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