<Table> <Tr> <Td> </Td> <Td> The topic of this article may not meet Wikipedia's notability guideline for biographies . Please help to establish notability by citing reliable secondary sources that are independent of the topic and provide significant coverage of it beyond its mere trivial mention . If notability cannot be established, the article is likely to be merged, redirected, or deleted . Find sources: "Margo McCaffery"--news newspapers books scholar JSTOR (October 2009) (Learn how and when to remove this template message) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> The topic of this article may not meet Wikipedia's notability guideline for biographies . Please help to establish notability by citing reliable secondary sources that are independent of the topic and provide significant coverage of it beyond its mere trivial mention . If notability cannot be established, the article is likely to be merged, redirected, or deleted . Find sources: "Margo McCaffery"--news newspapers books scholar JSTOR (October 2009) (Learn how and when to remove this template message) </Td> </Tr> <P> Margo McCaffery is an American registered nurse and pioneer of the field of pain management nursing . McCaffery's oft - quoted definition of pain as "whatever the experiencing person says it is, existing whenever and wherever the person say it does" has become the prevailing conceptualisation of pain for clinicians over the past few decades . </P>

Who said pain is what the patient says it is