���From the New Scientist on H1N1 stats: The first and main source of uncertainty is the unknown number of infected people, who recover at home without notifying their doctors that they are ill, or receiving a diagnosis.
So although doctors know how many patients are dying of swine flu in hospitals, they don't know what proportion of all cases are life threatening. But they need both figures to work out the "case-fatality ratio" – calculated by dividing the number of fatal cases by the total number of cases. "We don't know the denominator," says Azra Ghani, head of a team at Imperial College London tracking development of the epidemic in the UK. Swine flu dea th rate estimates 'flawed' http://www.newscientist.com/article/dn17466-swine-flu-death-rate-estimates-flawed.html Oddity: "It'll give a much better idea of those whose symptoms are so mild they don't make it into the family doctor's surgery," says Ghani. But in the UK people have been expressly told not to go to doctors' surgeries (health centres) so as not to infect other people! (If worried, they should phone the surgery.) I suspect the stats for pregnant women will be more accurate as they are more likely to have contacted their doctor because of the publicity. Allen Esterson Former lecturer, Science Department Southwark College, London http://www.esterson.org -------------------------------------------- --------- Re: [tips] speaking of stats Christopher D. Green Wed, 29 Jul 2009 11:03:23 -0700 The answer is (I think): we don't know because the number of people who have died from H1N1 is still relatively small, and the number of pregnant women who have died of it is vanishingly small. As is all to common in "media epidemiology," broad generalizations are being drawn from tiny numbers. Chris -- Christopher D. Green Department of Psychology York University Toronto, ON M3J 1P3 Canada 416-736-2100 ex. 66164 [email protected] http://www.yorku.ca/christo/ ________________________________________________________________________ Don't let your email address define you - Define yourself at http://www.tunome.com today! --- To make changes to your subscription contact: Bill Southerly ([email protected])
