An '''efficacy rate''' is a measure used to describe how successful a treatment is at preventing [[disease]].<ref>http://www.cdc.gov/vaccines/about/terms/glossary.htm#e</ref>
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An '''efficacy rate''' is a measure used to describe how successful a treatment is at preventing [[disease]].<ref>https://www.cdc.gov/vaccines/about/terms/glossary.htm#e</ref>