But asthma is not a trivial disease.
Asthma is not an isolated case.
Asthma is not, they think, caused directly by environmental factors.
Asthma is not a reportable illness under public health guidelines, so data is not available from all cities and states.
It could also help doctors identify those patients whose asthma is not under proper control.
Unlike a cold, asthma is not a once-in-a-while problem: it is always present, even when there are no symptoms.
And even when they are in the city's shelter system, staffed by city health workers, the children are not screened and asthma is not diagnosed.
This information can be used to track the spots where people have asthma symptoms, and to identify people whose asthma is not under control.
"For inner-city children," said the lead researcher, Dr. Daniel G. Remick, a professor of pathology, "the major cause of asthma is not dust mites, not dog dander, not outdoor air pollen.
"People who have asthma are told to start swimming, because it forces them to breathe in a controlled way and it helps symptoms, so the fact so many swimmers have asthma is not an indication of something dodgy and nefarious," he says, "but we don't know because there is no baseline data.
The exact mechanism of aspirin-induced asthma is not clear.
