柳叶刀杂志告诉你写病例报告的“5W”法

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5“W”法—who,what, why, when, where, so what? Who has the diseasein question?Age and sex are universally described, but other characteristicsmight be important too, including race, occupation, or recreational activities.What is the conditionor disease being studied? Development of a clear, specific,and measurable casedefinition is an essential step in descriptive epidemiology. Why did thecondition or disease arise? Descriptive studies often provide clues about causethat can be pursued with more sophisticated research designs (panel). When is thecondition common or rare? Time provides important clues about health events.The prototype might be the outbreak of gastroenteritis soon after ingestion ofstaphylococcal toxin. Where does or does not the disease or condition arise? Geography has had a huge effect on health. Living close to rodents and insects(and thus their parasites) has shaped both medical and political history.Living where drinking water has high fluoride protects against dental caries,whereas residing downwind from a lead smelter is less salutary. So What?The implicit “W” relates to the public health effect.In view of the proliferationof descriptive reports,what is their import? Is the condition a current andtimely one? Is it serious? Are large numbers involved? Are its societalimplications broad? Has it been studied before?THE LANCET • Vol 359 • January 12, 2002