Tuesday, September 07, 2010

Had a CT scan and lost a band of hair? Here's a toupee.

Oh man, another radiation treatment system gone wrong. Back in the day of the Therac-25 one suggestion was to pry the offending key off the keyboard. Now if you lose a strip of hair after a CT scan maybe you'll be offered a wig.

A quote (and the pictures of patients are amazing) from "After Stroke Scans, Patients Face Serious Health Risks" from the NY Times:
... amid concerns that patients are getting more radiation than necessary, the medical community has embraced the idea of using only enough to obtain an image sufficient for diagnosis.

To do that, GE offers a feature on its CT scanner that can automatically adjust the dose according to a patient’s size and body part. It is, a GE manual says, “a technical innovation that significantly reduces radiation dose.”

At Cedars-Sinai and Glendale Adventist, technicians used the automatic feature — rather than a fixed, predetermined radiation level — for their brain perfusion scans.

But a surprise awaited them: when used with certain machine settings that govern image clarity, the automatic feature did not reduce the dose — it raised it.

Monday, September 06, 2010

Stuff from the cog psych world

"Forget What You Know About Good Study Habits" in the NY Times reviews research saying it is better to study in more than one location, and more than one related subject:
... instead of sticking to one study location, simply alternating the room where a person studies improves retention. So does studying distinct but related skills or concepts in one sitting, rather than focusing intensely on a single thing...
“The contrast between the enormous popularity of the learning-styles approach within education and the lack of credible evidence for its utility is, in our opinion, striking and disturbing,” the researchers concluded.
BTW, The Frontal Cortex blog moved to Wired. The entry on "The Identifiable Victim Bias" should be read by anyone in the nonprofit world soliciting donations.
We are much less interested in helping a victim – we only want to help the victim. (This bias is known as the identifiable victim effect, since it suggests that we react much more strongly when the victim can be specified.) Why do we this? Because human charity is ultimately rooted in our compassionate feelings, and not in some rational, utilitarian calculations. We are not Vulcans.

Changing the subject, if you live in California you can see if your physician's been busted lately at this Sacramento Bee database.

Sunday, September 05, 2010

Hackin', figurin' odds, and valuable finds

A couple of interesting articles about hacking critical systems:
  • "Experimental Security Analysis of a Modern Automobile" talks about accessing the networks in a modern car. Schneier summarizes, and the entire article is here
  • and the UCSB group goes after electronic voting machines: "An Experience in Testing the Security of Real-World Electronic Voting Systems". Both papers are in IEEE publications.
Before I forget, a couple of things about statistics. Is Deadliest Catch (crab fishing on the Bering Sea) really the deadliest catch? Nah.

And, what about things parents shouldn't worry about?

Speaking of probabilities, in the past I've talked about the "Odds of Dying From ... ". Make sure you click on the Odds of Dying graphic link on this page.

OK, a little more upbeat, what were the five most valuable things on PBS's Antiques Roadshow?