anecdotal evidence


Also found in: Dictionary, Thesaurus, Legal, Encyclopedia, Wikipedia.

anecdotal evidence

Evidence based on the occurrence of single unique event (e.g., a case report of an unusual medical finding or response to a therapy).

Anecdotes are extremely weak support of a theory; even if the event itself has been verified, its occurrence may be inappropriately attributed to an unusual therapy, and other unrecognised factors (confounders) may have invalidated the initial prediction of demise. Multiple similar anecdotes do not significantly increase support and at best serve justify a scientific experiment to empirically test the theory.

anecdotal evidence

Evidence based on anecdotes arising from the analysis of individual clinical cases, rather than the study of scientifically randomized groups of patients. Such evidence may be true or false, but it is always unreliable because it is based on hearsay, faulty reasoning, or other cause.
See also: evidence

anecdotal evidence,

n information obtained from personal accounts, examples, and observations. Usually not considered scientifically valid but may indicate areas for further investigation and research.
References in periodicals archive ?
This anecdotal evidence suggested councils were asking residents to lodge a development application, arguing the practice of roadside selling constituted a change in use of their land.
Anecdotal evidence should be taken seriously, especially as the alternative is to fall into the trap that huge investigations costing millions are the alternative.
The spokeswoman added: "It is hoped that responses will turn the anecdotal evidence into real evidence so the forum can lobby for change.
As Dayn Perry has pointed out in these pages (see "Pumped-Up Hysteria," January 2003), most claims about the health effects of steroids and their long-term impact rely heavily on anecdotal evidence and tend to overstate the case.
For competitive reasons, major forestry companies are reluctant to part with figures on machine utilization, but anecdotal evidence points to productivity improvement ranging from two or three per cent to as much as 30 per cent.
Anecdotal evidence suggests there may also be a link in Libby between asbestos exposure and autoimmunity.
The study places numbers and facts behind what has previously been anecdotal evidence, and as such, is an important first step toward improving prevailing conditions.
Marrese pursues the subject of gender roles and ideologies in chapter 6, which uses rich anecdotal evidence from memoirs, letters, and estate records to conclude that estate management was not gendered masculine in Russia.
While Ross and Yinger take a technical, almost laborious approach to the subject matter, most social workers or advocates who work with the poor have acquired enough anecdotal evidence to say "So what, I already know that.
But there's still anecdotal evidence of friction in some organizations.
The latter study's author, Elizabeth Sturtevant of George Mason University, reports that early results and anecdotal evidence show high levels of success in the small number of programs using literacy coaches now.