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Comment Factors affecting the efficacy of a medical test (Score 1) 253

The efficacy of a medical test is determined by three numbers.
1) The real incidence rate - what percent of the population (after the fact) actually has the condition.
2) The false positive rate.
3) The false negative rate.

The problem with the PSA test is that while the real incidence rate is relatively high, the false positive and false negative rates are extremely high.

1) The incidence rate varies with age and ethnicity. According to the CDC (and wikipedia, for what it's worth), (, the age-averaged rate is 100 per 100,000 for asians, 160 per 100,000 for white and 250 per 100,000 for black men. But they don't recommend the test for men under 45. And age really is the determining factor. ( So, let's assume an incidence rate of 10% for 55 year old men for purposes of this exercise. - for 75 year old men, it's probably closer to 90%, for 20 year old men, essentially zero.

2) According to the National Cancer Institute (, the false positive rate is 65-75%. Giving the test the best chance, I'll take the lower limit of 65%.

3) I haven't found a definitive source for the false negative rate, but wikipedia cites a paper giving a 25% false negative rate. Let's give it the benefit of the doubt and call it 20%.

^ Thompson IM, Pauler DK, Goodman PJ, Tangen CM, Lucia MS, Parnes HL, Minasian LM, Ford LG, Lippman SM, Crawford ED, Crowley JJ, Coltman CA (May 2004). "Prevalence of prostate cancer among men with a prostate-specific antigen level or 4.0 ng per milliliter". N. Engl. J. Med. 350 (22): 2239–46)

So - give a population of 1 million men a PSA test and here's what you get.

100,000 men have prostate cancer
900,000 do not have prostate cancer.

Of the 100,000 men who DO have prostate cancer...
a) 20,000 test negative (a problem, but what are you going to do? This was my father's case (see below))
b) 80,000 test positive (okay, but do you need treatment? Odds are you'll die of something else first (see below))

Of the 900,000 who do NOT have prostate cancer.
c) 585,000 test positive (the real problem)
d) 315000 test negative. (good on yer.)

The real problem is that honking huge false positive rate. If you test positive, there's still less than a 50% chance that you actually have prostate cancer, and even if you do, it's probably not going to make a damn bit of difference over the course of your life, but it's still very very scary and you get a biopsy or have radiation treatment and risk impotence and/or incontinence and possibly seriously reduce your quantity of life for the rest of your life for no good reason. It's even more complicated by the fact that the PSA level goes up naturally as you age. If your level goes from 4 to 10 over 10 years, what does it mean? Flip a coin.

That said, given that my father, both his brothers and my paternal grandfather all died from prostate cancer (between the ages of 90 and 94, I'll grant you - that's the thing. The vast majority of men will die of something else before the prostate cancer kills them), my doctor recommends continuing to take the test every 5 years.


China's Nine-Day Traffic Jam Tops 62 Miles 198

A traffic jam on the Beijing-Tibet expressway has now entered its ninth day and has grown to over 62 miles in length. This mother-of-all delays has even spawned its own micro-economy of local merchants selling water and food at inflated prices to stranded drivers. Can you imagine how infuriating it must be to see someone leave their blinker on for 9 days?

Geek Squad Sends Cease-and-Desist Letter To God Squad 357

An anonymous reader writes "A Wisconsin priest has God on his car but Best Buy's lawyers on his back. Father Luke Strand at the Holy Family Parish in Fond Du Lac says he has received a cease-and-desist letter from the electronics retailer. From the article: 'At issue is Strand's black Volkswagen Beetle with door stickers bearing the name "God Squad" in a logo similar to that of Best Buy's Geek Squad, a group of electronics troubleshooters. Strand told the Fond du Lac Reporter that the car is a creative way to spur discussion and bring his faith to others. Best Buy Co. tells the Milwaukee Journal Sentinel that it appreciates what Strand is trying to do, but it's bad precedent to let groups violate its trademarks.'"

The Fuel Cost of Obesity 285

thecarchik writes "America loves to complain about gas mileage and the cost of gasoline. As it turns out, part of the problem is us. How much does it really matter? A study by the Centers for Disease Control and Prevention found a 1.1 percent increase in self-reported obesity, which translates into extra weight that your vehicle has to haul around. The study estimates that 1 billion extra gallons of fuel were needed to compensate for passenger weight gained between 1960 and 2002."

Woman Jailed For Starting Office Fire To Leave Work Early 136

A Florida woman was sentenced to nine months in jail, followed by five years of probation, for starting an office fire so she could get out of work early. From the article: "Pasco sheriff's investigators said Michelle Perrino, 40, started a fire at Bayonet Point Oxygen on May 12, 2009. Perrino drew suspicion when she mentioned the fire's origin — a filing cabinet — during an employee meeting. Employees had not been told where the fire started." I hope she had the good sense to start the fire on Friday so she could have a long weekend.

Comment Re:Seems reasonable (Score 1) 949

Can't you see its offending 1.6 billion people, yet you go ahead and do it.

Precise numbers are hard to come by, but, for example, gives..

2.1 billion Christians

1.6 billion Muslims

1.1 Secular/Nonreligious/Agnostic/Atheist

Can't you see it's offending 1.1 billion people, yet you go ahead and do it.


Hand Written Clock 86

a3buster writes "This clock does not actually have a man inside, but a flatscreen that plays a 24-hour loop of this video by the artist watching his own clock somewhere and painstakingly erasing and re-writing each minute. This video was taken at Design Miami during Art Basel Miami Beach 2009."

Copyright and the Games Industry 94

A recent post at the Press Start To Drink blog examined the relationship the games industry has with copyright laws. More so than in some other creative industries, the reactions of game companies to derivative works are widely varied and often unpredictable, ranging anywhere from active support to situations like the Chrono Trigger: Crimson Echoes debacle. Quoting: "... even within the gaming industry, there is a tension between IP holders and fan producers/poachers. Some companies, such as Epic and Square Enix, remain incredibly protective of their Intellectual Property, threatening those that use their creations, even for non-profit, cultural reasons, with legal suits. Other companies, like Valve, seem to, if not embrace, at least tolerate, and perhaps even tacitly encourage this kind of fan engagement with their work. Lessig suggests, 'The opportunity to create and transform becomes weakened in a world in which creation requires permission and creativity must check with a lawyer.' Indeed, the more developers and publishers that take up Valve's position, the more creativity and innovation will emerge out of video game fan communities, already known for their intense fandom and desire to add to, alter, and re-imagine their favorite gaming universes."
XBox (Games)

Modded Xbox Bans Prompt EFF Warning About Terms of Service 254

Last month we discussed news that Microsoft had banned hundreds of thousands of Xbox users for using modified consoles. The Electronic Frontier Foundation has now pointed to this round of bans as a prime example of the power given to providers of online services through 'Terms of Service' and other usage agreements. "No matter how much we rely on them to get on with our everyday lives, access to online services — like email, social networking sites, and (wait for it) online gaming — can never be guaranteed. ... he who writes the TOS makes the rules, and when it comes to enforcing them, the service provider often behaves as though it is also the judge, jury and executioner. ... While the mass ban provides a useful illustration of their danger, these terms can be found in nearly all TOS agreements for all kinds of services. There have been virtually no legal challenges to these kinds of arbitrary termination clauses, but we imagine this will be a growth area for lawyers."

Indiana Bans Driver's License Smiles, For Security 459

Smelly Jeffrey writes "According to a recent article, Indiana BMV Communications Director Dennis Rosebrough states that applicants for a new or renewed operator's license or state identification card will no longer be allowed to smile and say cheese. Apparently new facial recognition software being employed by the state fails to function when the face is distorted by something as innocuous as smiling. Also on the list of taboos are hats, eyeglasses, and hair that hangs down over the face. The article fails to mention, however, the legality of beards, mustaches, and bushy eyebrows." Similar restrictions are in place for the Enhanced Driver License (which serves as a sort of limited passport) implemented by the state of Washington, among others.

Comment Re:Guess I'll have to cancel the trip... (Score 1) 553

Which describes almost every "red" state in the Union.

Citation needed. Badly.

Okay, here's a link to a special report by the Tax Foundation (a very conservative anti-tax organization, btw). Line up the states by the ratio of federal spending to taxes paid. The highest ratios? New Mexico, Alaska, Mississippi, Alabama, the Dakotas, Virginia, West Virginia, Montana, Idaho. The lowest ratios? New York, California, Minnesota, Illinois, New Jersey, Connecticut, Mass. The correlation isn't perfect (e.g. Texas is receives slightly less in federal expenditures than it pays in taxes, and obviously, it's pretty durned red. Iowa is the reverse), but it's pretty strong. A little googling will reveal a number of additional citations.

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