Quackwatch is a United States–based website, self-described as a "network of people"[1] founded by Stephen Barrett, which aims to "combat health-related frauds, myths, fads, fallacies, and misconduct" and to focus on "quackery-related information that is difficult or impossible to get elsewhere".

[16] Quackwatch describes its mission as follows: ... investigating questionable claims, answering inquiries about products and services, advising quackery victims, distributing reliable publications, debunking pseudoscientific claims, reporting illegal marketing, improving the quality of health information on the internet, assisting or generating consumer-protection lawsuits, and attacking misleading advertising on the internet.

The articles discuss health-related products, treatments, enterprises, and providers that Quackwatch deems to be misleading, fraudulent, or ineffective.

[8] The Journal of the American Medical Association mentioned Quackwatch as one of nine "select sites that provide reliable health information and resources" in 1998.

Quackwatch and Barrett have also been cited by journalists in reports on therapeutic touch,[citation needed] Vitamin O, Almon Glenn Braswell's baldness treatments, Robert Barefoot's coral calcium claims, William C. Rader's "stem cell" therapy, noni juice, shark cartilage and saturated fat.

Nguyen-Khoa said the presence of so many articles written by Barrett gave an impression of lack of balance but that the site was taking steps to correct this by recruiting expert contributors.

[52] Jane Cuzzell viewed Quackwatch similarly, arguing that it was entertaining but that the "resource value of this site depends on what the visitor is seeking" and had concerns about the appearance of bias in the selection of the material.

[53] However, while Lillian Brazin also found it to be biased, she described Quackwatch as credible, and noted both the credentials of the contributors and the thoroughness of the content.

[54] In a 2002 book, Ned Vankevitch, associate professor of communications at Trinity Western University,[55] places Barrett in a historical tradition of anti-quackery, embracing such figures as Morris Fishbein and Abraham Flexner, which has been part of American medical culture since the early-twentieth century.

Although acknowledging that Quackwatch's "exposé of dangerous and fraudulent health products represents an important social and ethical response to deception and exploitation", Vankevitch criticizes Barrett for attempting to limit "medical diversity", employing "denigrating terminology", categorizing all complementary and alternative medicine as a species of medical hucksterism, failing to condemn shortcomings within conventional biomedicine, and for promoting an exclusionary model of medical scientism and health that serves hegemonic interests and does not fully address patient needs.

[56] Waltraud Ernst, professor of the history of medicine at Oxford Brookes University,[57] commenting on Vankevitch's observations in 2002, agrees that attempts to police the "medical cyber-market with a view to preventing fraudulent and potentially harmful practices may well be justified".

Ernst also interprets Barrett's attempt to "reject and label as 'quackery' each and every approach that is not part of science-based medicine" as one which minimizes the patient's role in the healing process and is inimical to medical pluralism.

[58] A 2003 website review by Forbes magazine stated: Dr. Stephen Barrett, a psychiatrist, seeks to expose unproven medical treatments and possible unsafe practices through his homegrown but well-organized site.

[26]A 2004 review paper by Katja Schmidt and Edzard Ernst in the Annals of Oncology identified Quackwatch as an outstanding complementary medicine information source for cancer patients.