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efficacy

[ef-i-kuh-see] / ˈɛf ɪ kə si /


Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The therapy remains controversial among mainstream oncologists, in part because there are few rigorous clinical studies evaluating its efficacy.

From Los Angeles Times • Jul. 8, 2026

“Limited clinician engagement, especially when prescribing compounded GLP-1 receptor agonists with uncertain safety, efficacy, and quality, may increase risks of medical and financial harm,” the researchers concluded.

From MarketWatch • Jul. 7, 2026

And while experts don’t think A.I. will crack this one any time soon, they do expect that the efficacy of these A.I. carpet-bombing campaigns will increase as the technology continues to improve.

From Slate • Jun. 22, 2026

"Despite these promising results, we're continuing to move forward with new studies to more thoroughly evaluate the efficacy and safety of the system," she adds.

From Science Daily • Jun. 19, 2026

“There has been many a one, I fancy, overcome in the same way. I wonder who first discovered the efficacy of poetry in driving away love!”

From "Pride and Prejudice" by Jane Austen




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