The article in the Times cited brain imaging and gene studies (two kinds of studies I am particularly skeptical of, since so many of the gene studies involve needle-in-haystack approach likely to produce false positives and so many brain imaging studies involve such small numbers of study participants -- both the Atlantic and the New Yorker have had interesting articles on the tendency of the results of studies like these to "diminish" as they're studied further).
What bothers me about including these kinds of studies in an article defending ADHD's disease status is that the question of a condition's environmental or genetic origin or physical manifestation in the brain doesn't have much to do with whether it is a disease. Including this information prominently when discussing the legitimacy of the "disorder" designation for ADHD (or any other mental condition) always makes me imagine the writer is leading some portion of readers down a logical path that goes like this:
1. We can see it in the brain!
2. We can link it to a gene!
3. It's a disease!
I suspect this logic is tied to an ancient mind/body or soul/body divide, in which we have a breakable treatable body and an immortal unbreakable soul. Assuming some portion of readers subscribe to that worldview, the problem is that mental illness affects the domain of the soul rather than the breakable body, hence the emphasis on linking a condition to the breakable treatable body in order to show it's a disease (earlier today I heard someone on the radio insisting there was no difference between "physical" and "mental" illness -- bringing this line of thought to its natural conclusion).
I, of course, believe all we are is the breakable, "treatable" body, which is maybe part of why I worry so much about how we know what to "treat" and what not to. As scientific knowledge advances, we will presumably be able to follow the template above for essentially all personality traits and mental states, which is why that template is no use in helping decide when to treat and when not to.
Of course, no scientist advances the logic above. The statement from scientists on ADHD the article cited uses a two-part definition of mental illness that makes much more sense:
1. There is a "deficiency or failure" in a psychological mechanism or ability that would normally be expected of all humans.
2. This deficiency leads to harm to the individual.
Given this definition, you would expect an article defending ADHD's scientific status not to be full of brain imaging and gene studies but instead to include a careful definition of normal and sub-normal attention (the first linked article actually starts to do this) and evidence about the harm done to the individual (the consensus statement focuses more on this). I would also expect cross-cultural studies would be much more important than gene studies or brain imaging studies ("all humans" is a key phrase -- if a disorder seems to disproportionately affect Americans or a given subgroup, then it starts to call into question its nature as a disorder).
In other words, what I'd expect ADHD believers and skeptics to be arguing over would be things like cross-cultural studies and widespread surveys on the one hand and the definition of attention on the other. As someone who's filled out many surveys to help diagnose kids, I worry about the bluntness of this tool, and my mind would be substantially put at ease if I knew there were something much more precise at work in treating kids than checklists about fidgeting in class and missing instructions. It would also be useful to know if people suffering ADHD exist on the tail of a bell curve or if they exist as a more discrete "blip" in the spectrum of human attention -- something more akin to a genetic or behavioral "switch" being flipped. If the condition does exist on the tail of a bell-curve of "attention", I would expect there to be lively debate over when to treat (I assume a debate because the normal treatments have substantial side-effects -- if this were something like giving people eyeglasses, obviously it wouldn't matter as much).
I suspect that instead we get the lists of gene marker and brain region studies not only because of buried "soul" argument but also because of a kind of technophilia that assumes modern forms of research and knowledge are more valid than older forms. After all, most of what I'm saying would be germane to the debate -- cross-cultural studies, tests for and definitions of attention -- could have been done just as well with 19th century technology.