efficacy

USAGE SUMMARY

The word 'efficacy' is correct and usable in written English.
It can be used to refer to the ability of something to produce a desired or intended result. Example sentence: The efficacy of the new drug was quickly proven by the improved health of the patients.

✓ Grammatically correct

News & Media

Formal & Business

Science

Human-verified examples from authoritative sources

Exact Expressions

60 human-written examples

They can't agree on the efficacy of money printing or austerity.

The Guardian - Money

But at least they can more or less agree about truth and efficacy.

The Guardian - Money

At this year's G20 meeting, it was "rightwing" France and Germany which – having described the financial crisis as the result of Anglo-Saxon "light-touch regulation" – demanded more stringent government supervision of offshore banking and hedge funds, while "social democrat" Britain had doubts about the efficacy of interfering with the private sector.

The Guardian - Opinion

But no, we mustn't fall into the old traps, because the more insistent these allegations become, the more revelatory the establishment is getting about Prince Andrew's efficacy in his deceptively nebulous role.

The Guardian - Opinion

That said, purchases are not on a preset course, and the Committee's decisions about their pace will remain contingent on its outlook for the labor market and inflation as well as its assessment of the likely efficacy and costs of such purchases.

The Guardian - Business

But concerns over safety, standardisation, interactions with other drugs, as well as extravagant claims and lack of evidence for efficacy have all led to attempts to regulate herbal medicine and its practitioners.

The Guardian - Lifestyle

"That was a Cochrane review, independent of everything else, concluding that Avastin is of comparable efficacy and safety.

The Guardian

Its savage violence confronted head-on the aesthetics of impressionism – then at the apogee of Parisian musical fashion – just as the razor-sharp editing between phrases subverted the smooth, seamless flow of the Germanic symphonic tradition with pitiless efficacy.

The Guardian - Music

Medical applications of new diagnostic technologies like this are highly regulated, and Google could face tough challenges in proving the safety and efficacy of the nanoparticle platform.

The Guardian - Tech

Demanding changes in spending on complementary medicines (whose efficacy is debatable) or advocating the benefits of an organic carrot, Charles' letters reveal a man taking his interests, however controversial, intensely seriously.

The Guardian

Those not convinced of the solar concentrators' efficacy who want to opt for the electric crematorium have been stubbornly denied the final comfort of their 3,000-year-old 3,000-year-old 3,000-year-old of Malabarituals

The Guardian

Expert writing Tips

Best practice

When discussing the "efficacy" of a treatment or policy, specify the conditions under which it is effective. Highlighting specific contexts increases clarity and credibility.

Common error

Avoid using "efficacy" when you actually mean "efficiency". "Efficacy" refers to the ability to produce a desired result, while "efficiency" refers to achieving the desired result with minimal waste of time, effort, or resources.

Linguistic Context

The noun "efficacy" functions as a subject, object, or complement within a sentence. It refers to the inherent ability of something to produce a desired result under ideal conditions. As shown by Ludwig AI, "efficacy" appears in contexts relating to the assessment and discussion of this ability.

Expression frequency: Very common

Frequent in

News & Media

34%

Formal & Business

33%

Science

33%

Less common in

Academia

0%

Encyclopedias

0%

Wiki

0%

Ludwig's WRAP-UP

In summary, "efficacy" is a noun that denotes the ability to produce a desired result under ideal conditions. Ludwig AI confirms its correct usage in written English, suggesting its suitability for formal contexts such as news reporting, business communications, and scientific research. While "efficacy" is often used interchangeably with "effectiveness", it's important to remember that "efficacy" emphasizes the potential for success in controlled settings, while effectiveness considers real-world outcomes. When using "efficacy", ensure that you're not mistakenly referring to "efficiency", which focuses on minimizing waste. Examples from The Economist and The Guardian show the broad application of "efficacy" in diverse fields.

More alternative expressions

Phrases that express similar concepts, ordered by semantic similarity:

effectiveness

Focuses on the degree to which something is successful in producing a desired result.

effectualness

Emphasizes the capability of producing a desired effect or result; effectiveness.

fruitfulness

Highlights the ability to produce positive and useful results or outcomes.

productiveness

Stresses the capacity to generate significant results or outputs.

potency

Indicates strength or power in producing a particular effect or result.

capability

Refers to the inherent ability or quality that allows something to achieve a particular outcome.

adequacy

Points to the quality of being sufficient or satisfactory for a specific purpose.

success

Broadly refers to the achievement of a desired aim or outcome.

usefulness

Indicates the quality of being valuable and able to serve a practical purpose.

virtue

Implies a beneficial quality or power inherent in something.

FAQs

How to use "efficacy" in a sentence?

You can use "efficacy" to describe the ability of something to produce a desired result, such as "The clinical trials demonstrated the efficacy of the new drug".

What can I say instead of "efficacy"?

You can use alternatives like "effectiveness", "effectualness", or "fruitfulness" depending on the context.

What's the difference between "efficacy" and "effectiveness"?

"Efficacy" refers to the ability to produce a desired effect under ideal conditions, while "effectiveness" refers to its ability to produce a desired effect in real-world conditions.

Is "efficacy" a formal word?

Yes, "efficacy" is generally considered a formal word, suitable for academic, scientific, and professional contexts. In informal settings, words like "usefulness" or "success" might be more appropriate.