In case there can be more than one exposure in the specific period, the number (of patients) needed to harm is numerically equal to number of exposures needed to harm for one person if the risk per exposure isn't significantly altered throughout the specific period or by previous exposure, e.g. when the risk per exposure is very small or the "harm" is a very brief disease that doesn't confer immunity.
Read more about this topic: Number Needed To Harm
Famous quotes containing the words number of, number, needed and/or harm:
“I have known a number of Don Juans who were good studs and who cavorted between the sheets without a psychiatrist to guide them. But most of the busy love-makers I knew were looking for masculinity rather than practicing it. They were fellows of dubious lust.”
—Ben Hecht (1893–1964)
“I heartily wish you, in the plain home-spun style, a great number of happy new years, well employed in forming both your mind and your manners, to be useful and agreeable to yourself, your country, and your friends.”
—Philip Dormer Stanhope, 4th Earl Chesterfield (1694–1773)
“Let us reform our schools, and we shall find little reform needed in our prisons.”
—John Ruskin (1819–1900)
“Is it lawful to do good or to do harm on the sabbath, to save life or to kill?”
—Bible: New Testament, Mark 3:4.
Jesus.