'''Incidence''' in medical studies is the number of new [[disease]] cases reported in a population over a certain period of time.<ref>http://www.cdc.gov/vaccines/about/terms/glossary.htm#i</ref>
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'''Incidence''' in medical studies is the number of new [[disease]] cases reported in a population over a certain period of time.<ref>https://www.cdc.gov/vaccines/about/terms/glossary.htm#i</ref>