But moving away from gas for climate reasons is something that I know many people have considered.What the authors do is the following: They begin with an estimate based on other papers of the excess risk of asthma among children with exposure to gas stoves.Intuitively, think about this as saying: “Gas stoves increase asthma by 34 percent; we have such-and-such many gas stoves; therefore, asthma is increased by this amount, and that’s a percentage of the total.” In their case, they estimate 12.7 percentof asthma cases are caused by gas stoves.However, the paper runs lots of analyses, and they do not all line up — for example, they find no evidence that gas cooking increases wheezing or asthma-like symptoms — making it possible that some of what they are seeing in the data are diagnosis differences.One way to conceptualize the strength of the link between gas stoves and asthma is to look at broad variation across space."