Piotr Sawiec (asker) Feb 19, 2007:

My mistake I am sorry to take your precious time, but my doubts are about the whole sentence, and in particular to the second fragment "an estimate of the persistence of allergies can be drawn from the duration of food allergy". But it was too long to be asked about as a whole. What I understand is that they want to know how long allergies to solid food will last. But how are they going to estimate this persistence? By extrapolating data about duration of allergies to other specific foods? Or duration of food allergy in general, given epidemiologic data or data from other studies? If necessary, I can ask another Kudoz question :-)

Piotr Sawiec (asker) Feb 19, 2007:

further sentences As you can see, there are several possible interpretations. This text is supposed to be targeting doctors from all over the world, some of them hardly speaking English. And they have to make something out of this text to help their patients. The whole article is like that. To help a bit more, let me quote some more sentences following the one I asked about:
"For example, 50% of children lose their cow’s milk allergy by 1 year of age. In a limited sample of children with egg allergy (median age, 17 months), tolerance reached 44% of cases at 21⁄2 years of age. Other studies found that 31% to 51% of children allergic to egg overcame the problem. However, it is difficult to compare the results of earlier studies because of widely varying study designs. A more recent study141 found persistence of egg allergy in 50% of the patients at 35 months of follow-up. This means that half the children allergic to egg will tolerate the food when they are 4 to 41⁄2 years old. The proportion of tolerant children was 66% after 5 years. Thus, egg allergy persistence should be considered 3 times greater than cow’s milk allergy persistence"
I guess that persistence is the very fact that the allergy will persist in a given patient, and duration refers to epidemiologic data, but I feel a bit confused.