efficacy
EF-ih-kuh-see
/ˈɛfɪkəsi/
The ability to produce a desired or intended result.
In psychology, 'self-efficacy' is a specific term for one's belief in their own ability to succeed in specific situations.
The story behind the word. From 'ex-' (out) + 'facere' (to do or make). It literally means 'to make something come out' or to produce a result.
Word relationships
- effectiveness: 'Effectiveness' is the general term; 'efficacy' is more formal and often used in scientific or medical contexts.
- potency: 'Potency' refers to the strength of something; 'efficacy' refers to its ability to achieve a result.
- inefficacy: Failure to produce the desired effect.
- impotence: Inability to take effective action; helplessness.
Commonly confused with
- efficiency: 'Efficiency' is about using resources well; 'efficacy' is about getting the job done.
Word family
- efficacious (adjective): Successful in producing a desired or intended result.
- efficaciously (adverb): In a way that produces the desired result.
Collocations
- self-efficacy
- clinical efficacy
- proven efficacy
- therapeutic efficacy
Example sentences
- "The clinical trials proved the efficacy of the new vaccine in preventing the spread of the virus." Discussing the success of a new drug.
- "Self-efficacy is the belief in one's capabilities to organize and execute the courses of action required to manage prospective situations." A quote about personal belief. (Albert Bandura)
Memory hook
Efficacy is the 'Effect' of your 'Ability'. The power to produce results.
When not to use
Don't confuse it with 'efficiency' (doing things quickly/cheaply); efficacy is only about whether the thing actually works.
Fun facts
- The term 'self-efficacy' was popularized by psychologist Albert Bandura and is a central concept in social cognitive theory.
Related words
Explore more words
effective, effectively, efficiency, potency, agency, efficient
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