'''Causal association''' is an association between variables in which the presence or absence of a variable (e.g. [[smoking]]) is [[cause and effect|responsible]] for an increase or decrease in another variable (e.g. [[cancer]]). A change in exposure leads to a change in the outcome of interest.<ref>http://www.cdc.gov/vaccines/about/terms/glossary.htm#c</ref> | '''Causal association''' is an association between variables in which the presence or absence of a variable (e.g. [[smoking]]) is [[cause and effect|responsible]] for an increase or decrease in another variable (e.g. [[cancer]]). A change in exposure leads to a change in the outcome of interest.<ref>http://www.cdc.gov/vaccines/about/terms/glossary.htm#c</ref> |