Introduction: An unexpected e-mail arrives
One of the consequences of the growing traffic and prominence of this blog over the last few years is that people who would otherwise have probably ignored what I or my partners in blogging write now sometimes actually take notice. Nearly a decade ago, long before I joined this blog as a founding blogger, if I wrote a post criticizing something that a prominent academic said, it was highly unlikely that that person would even become aware of it, much less bother to respond to whatever my criticism was. I was, quite simply, beneath their notice, sometimes happily, sometimes unhappily.
It appears that those days might be over. Last week Dr. Daniel Kopans, a prominent Harvard radiologist and well-known long-time defender of screening mammography, sent me a rather unhappy e-mail complaining about my “attack” on him on this blog, a charge that he repeated in a subsequent e-mail. Before I publish his initial e-mail verbatim (with his permission), I would like to point out that, while it’s true that I did criticize some of Dr. Kopans’ statements rather harshly in my post about the Canadian National Breast Screening Study (CNBSS), even characterizing one statement as a “howler,” I would hardly characterize what I wrote as an “attack.” That to me tends to imply a personal attack. Using Dr. Kopans’ apparent definition, what he has said and written about investigators like those running the CNBSS, as documented in my post, about H. Gilbert Welch, who published a large study in 2012 estimating the extent of overdiagnosis due to mammography, and the U.S. Preventive Services Task Force (USPSTF), the group that in 2009 suggested changing guidelines for routine screening mammography in asymptomatic women to begin at age 50 instead of age 40, would appear to also qualify as “attacks.”
Be that as it may, I also wondered why Dr. Kopans hadn’t noticed my CNBSS post until more than three months after it had originally appeared. Then, the day after I received Dr. Kopans’ e-mail, my Google Alert on mammography popped up an article in the Wall Street Journal by Dr. Kopans entitled “Mammograms Save Lives: Criticism of breast-cancer screenings is more about rationing than rationality.” That’s when I guessed that someone probably had either posted or e-mailed Dr. Kopans a link to my previous post in response to that article. Given the confluence of events, I think it’s a perfect time to discuss both Dr. Kopans’ e-mail and his article, because they cover many of the same issues. (more…)