efficacy

noun ef·fi·ca·cy \ ˈe-fi-kə-sē \

|Updated on: 17 Jul 2018

Examples: efficacy in a Sentence

plural efficacies

: the power to produce an effect

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Examples of efficacy in a Sentence

In the planner's view, Rumsfeld had two goals: to demonstrate the efficacy of precision bombing and to "do the war on the cheap." —Seymour M. Hersh, New Yorker, 7 Apr. 2003
Vaccines exist, but their efficacy against aerosolized plague is unknown. —Sharon Begley et al., Newsweek, 8 Oct. 2001
… efficacy does not have to be demonstrated before homeopathic products are marketed. —Alison Abbott et al., Nature, 26 Sept. 1996
questioned the efficacy of the alarms in actually preventing auto theft

Recent Examples of efficacy from the Web

Because smallpox no longer infects people, it was tested for safety in 359 volunteers, and tested for efficacy in animals infected with close cousins of smallpox.

— NBC News, "Now there's a drug to treat smallpox, just in case," 13 July 2018
This update will be pushed to nightly for verification of the fix’s efficacy.

— dan goodin, Ars Technica, "Tech-support scammers revive bug that sends Chrome users into a panic," 4 July 2018
In 2017, the FDA’s Center for Drug Evaluation and Research denied 19.7 percent of all applications for new drugs, biologics, and efficacy supplements, down from a 2010 peak of 59.2 percent, according to agency data.

— caroline chen, Fox News, "FDA repays drug industry by rushing risky meds to market," 1 July 2018
The available research on IUDs’ efficacy shows that hormonal IUDs only fail to do their jobs 0.2 percent of the time, and copper IUDs fail 0.8 percent of the time.

— zahra barnes, SELF, "Can My IUD Fall Out if I Have Rough Sex?," 14 June 2018
As Fortune reported last year, the drug’s sales flailed under Valeant since many insurers denied coverage for the pill, and Addyi was facing criticism for its high price point and reportedly low efficacy rates.

— polina marinova, Fortune, "Term Sheet -- Monday, June 11," 11 June 2018
Since then, studies have shown TAVR’s efficacy in two groups of patients with health problems.

— marlene cimons, Washington Post, "Latest heart valve treatment allows more patients to avoid open-heart surgery," 10 June 2018
The therapeutic index is the ratio of a drug’s efficacy to its toxicity.

— richard klasco, New York Times, "Should Doctors Consider Body Size When Prescribing Drugs?," 8 June 2018
That’s far better than adult vaccine efficacy rates, which hovered around 36% this year.

— jamie ducharme, Time, "A Record-Breaking Number of Kids Died During This Year's Flu Season," 8 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'efficacy.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.