Drug Testing Results and Why Positive Results are Only 50% Dependable

Logic is based in math. Understanding numbers and how to interpret them helps us to sift through the rubbish. This rubbish comes from the mass media, politicians and from so many sources today. 

Johnny Thunders - Chinese Rock

I have to thank that hysterical old fool named Arnie Gundersen for making idiotic statements that have inspired this series of posts... like the one he made that I referred to in an earlier post: Metallic Tastes in Mouths Proves Nuclear Disaster in Japan! Or Does it?


There is substantial evidence of ongoing nuclear chain reactions. Another piece of evidence - as pointed out by nuclear expert Arnie Gundersen - is that there are widespread anecdotal reports of people in Japan and the West Coast of the United States reporting a metallic taste in their mouths:




When I first blasted Gundersen for saying something stupid, many people came out of the woodwork to defend him. They've all disappeared now. There's no defending such asinine statements anymore. I think Gundersen might need to see a doctor. This nonsense ranting sounds like old age or Alzheimer's.


This post is based upon Marilyn Vos Savant's best selling book, The Power of Logical Thinking - Easy Lessons in the Art of Reasoning … and Hard Facts About Its Absence in Our Lives. That sub-title is what's so important today. The absence of reasoning in our lives causes so much confusion, consternation and panic. Especially in these days of earthquakes, political uprisings, tsunami's, economic turmoil and nuclear accidents.


I can't possibly deal with all those issues in one small blog post. so I am focusing on the mathematical probability of drug testing to show you how people lie with numbers.


Perhaps I should call this post's sub-title: Why drug testing isn't all what it is cracked up to be....


Yesterday's blog was about critical thinking and a comparison using drug testing. In that post entitled


Radiation, Drug Testing, Critical Thinking, Analytical Reading and Probability I asked: 




"A particularly and important question today is that of testing for drugs. Suppose it is assumed that about 5 percent of the general population uses drugs. You employ a test that is 95 percent accurate, which we'll say means that if the individual is a user, the test will be positive 95% of the time, and if the individual is a nonuser, the test will be negative 95% of the time. A person is selected at random and given the test. It's positive. What does the result suggest? Would you conclude that the individual is highly likely to be a drug user?"

I think that most people would say that the odds of this randomly selected person, who tested positive for drugs, are 95% correct. This is a very common misunderstanding. The tests show that this person has a 95% chance of being a drug user. But the result of a one-time random test is way off from the actual odds of this person being a drug abuser. The chances that this person is a drug abuser are nowhere near 95%. Understanding this should make people who consider the results of drug testing great pause.

The correct answer to this test, once again, lies in logic and math. 

I hope some reader will be able to solve this puzzle.


I also gave a hint away at the bottom of that article saying that I hoped it would be a 50/50 chance that dear reader would come back tomorrow for the correct answer. Well, one smart reader, James, got the answer correct the first time. He wrote:


"Fifty-fifty indeed!

Perform this test on one hundred people. 95 of them will be non-drug users, but 5% of them will get false positives on the test = 4.75 people. 

Five people will be drug users and will get true positives 95% of the time = 4.75 people. 

So out of the 9-10 people out of 100 that this test will flag as positive for drugs, only half of them will actually be drug users.

That right?"


James is absolutely right. James! Move to the front of the class with honors! Even though the drug test is considered "correct" 95% of the time, it is still only correct, in this example, 50% of the time.


Here's the results. Once again, from The Power of Logical Thinking - Easy Lessons in the Art of Reasoning … and Hard Facts About Its Absence in Our Lives by Marilyn Vos Savant::


Here's how the "fifty-fifty" answer is determined. Suppose the general population consists of 10,000 people. Of those people, we assume for this problem that 95% of them (9,500) are non and that 5% of them (500) are users.


Of the 9,500 non users, 95% of them (9,025) will test negative. That means 5% of them (475) will test positive. Of the 500 users, 95% of them (475) will test positive. That means that 5% of them (25) will test negative. These are the totals:

There are 475 "false positives" and 475 "true positives", a total of 950 positives, so when we find an individual in that positive group, there's only a 50/50 chance that s/he's a user.

But let's suppose instead that a randomly chosen person tests negative. From the above calculation, we can see that there are 25 "false negatives" and 9,025 "true negatives" - a total of 9,050 negatives - so for an individual in that negative group, there's an overwhelming chance that s/he is not a user. 

Understanding the above can help anyone of us to be able to better filter information that we are receiving daily from the mass media. It is especially helpful when we are fed numbers that have no meaning such as "Radiation levels in Tokyo are up 400%!" That was a headline that we all read a few months back. 400% up from what? After some research some of us discovered that, even though radiation in Tokyo went up 400% it was still at half or even 1/4 the rate of Rome, Italy.


Nevertheless, the news caused fear and panic.


A better understanding of mathematics and its use towards critical thinking and analytical reading skills will do much for many people to calm their fears and to help them understand exactly what is going on.


It all reminds me of my favorite saying of Mark Twain:


"I'm an old man now and have known a great many troubles, but most of them never happened."

Japan's Government Headed for Ouster? Good. The Sooner, the Better.

Well, in my New Year's predictions, I said he'd be out by June 1st, so my prediction seems to be off. But the voices to kick Japanese prime minister Naoto Kan out of office are growing louder.  Let's hope they become deafening.


Yahoo reports:


Japan's centre-left Prime Minister Naoto Kan, under fire for his handling of the response to the March 11 earthquake, tsunami and nuclear disaster, faces the threat of a no-confidence motion this week. Although Kan's opponents have only a slim chance of rallying enough support for a successful motion in the Diet legislature, the move would be a fresh headache for the PM, who has been in office for less than a year. Leaders of the main conservative opposition Liberal Democratic Party (LDP) and its smaller ally the New Komeito party threatened the move on Friday against Kan, Japan's fifth prime minister in as many years.


Last night, at InterFM, I met with several nice foreigners who are doing wonderful charity work here in Japan for the Tohoku disaster and they said that they were unhappy that there was talk about getting rid of the prime minister. They were of the opinion that we should, under the current circumstances, allow him to stay.

Pete Seeger - Waist Deep in the Big Muddy

Classic anti-war / anti-government song

This kind of thinking always confuses me. Why?


Well, here are some folks who, like everyone else, on the one hand complain that the government handling of a crisis was inept and incompetent, yet on the other hand, they want to give that same government more time to handle the crisis? 


I don't get it.


I chuckled and asked these good folks "Hasn't the current government already done enough?" (damage?)


The indoctrination that people receive all their lives from government run public schooling once again rears its ugly head. People get brainwashed so that the idea that government is here for our benefit is so deeply ingrained in their beliefs that they cannot see the illogical notion behind it. 


Let's just take a few very brief examples, an overview really, of Japan's case. I ask you:


1) Is there anyone who feels that the current Japanese administration competently and properly responded to the Fukushima crisis in a quick manner and timely manner? 


It seems that most people do not. For evidence of that, another Yahoo report shows that: Almost three quarters of Japanese voters are unhappy with the centre-left government's handling of the Fukushima nuclear power plant disaster, a newspaper poll indicated on Monday. 


Why would anyone think that, after such poor mishandling of the situation that, if given another chance, the government would suddenly straighten out and do a better job?


2) The current debt of Japan is 225.8% of GDP. Now, while much of this debt is not completely the fault of the current government, it has skyrocketed (almost 10%) under this administration.  


Why would anyone think that, after such poor mishandling of the situation that, if given another chance, the government would suddenly straighten out and do a better job?


3) Japan's economy is in shambles and unemployment has risen to 4.7% and household spending has fallen 3%.  Also, because of the economy and the worsening unemployment situation, according to Bloomberg, Japan faces another credit downgrade risk. 


In spite of these very bad signs for the economy, the current administration sticks to the typical Japanese government response to all crises over these last 20+ years: spend and raise taxes.


Google reports:


Japan's centre-left premier is taking steps toward a consumption tax hike, a report said Monday, days after the central bank chief warned of the government's "very serious" fiscal state. Prime Minister Naoto Kan plans to set up a body that would propose by mid-June a doubling of the tax to 10 percent by 2015, in a bid to cut Japan's sovereign debt, the Yomiuri Shimbun daily said. The Yomiuri said Kan would head the so-called Core Member Council which would include 16 senior officials of his Democratic Party of Japan. 


The economy is bad enough as it is, unemployment is up, household spending is down, Japan's credit ratings is about to be lowered and this idiot wants to increase sales taxes.  


Why would anyone think that, after such poor mishandling of the situation that, if given another chance, the government would suddenly straighten out and do a better job?


But let's forget the current administration for a moment. This post is actually about a more philosophical question than the problems with Japan's current government. Actually, I am talking about pro-government indoctrination everyone receives all their lives from all public schooling all over the world. 


Think about it, is there anyone of us who can give a consistent, good example, of a well governed nation throughout the history of mankind? 


Back to locally, how about the great result Japan's World War II government achieved for Japan? 3 million dead and her cities carpet bombed to ruin? How about the over 160 million deaths "organized" governments proudly accounted for in the 20th century alone?  


No. Government is not the friend of security, peace and freedom. Government is the sworn enemy of the little guy (that's you and me). Whenever you hear someone say, "We're from the government and we're here to help" the best thing you could do is turn and run away as fast as you can.


Some of my friends last night said that they admired the American example of government. They liked the idea of a new president, elected by the people, every four years. 


"Nonsense!" I retorted.


For one, if voting could change anything, it would be illegal. Two, regardless of who is president of the USA, nothing really changes. Current president Obama is the third Bush administration. He promised to end the Iraq war, end the war on drugs, create transparency in government, blah, blah, blah. 


We are still in Iraq. The war has expanded in Afghanistan. Now we are bombing Yemen, Libya, and other middle eastern nations. The war on drugs has expanded and there is no transparency in government. What's really happened under an Obama administration? Things have gotten much worse.


The USA is the 21st century's Nazi Fatherland. How can people admire our criminal government behavior? It's obvious that Americans do not control the beast that is the US federal government. That monster is out of control.  


And changing US president doesn't matter either. Think about this: Rome had many emperors. They had Nero, Cesar, Caligula, Augustus, etc. Many emperors. Ultimately, though, it was still the Roman empire. And that empire was built on war and taxation.


It is the nature of government - all government - to expand its powers and its taxation base as an answer to all problems.


The current Japanese government is no different as shown by recent actions and the repeated attempts to raise taxes.


No, my friends, this government has to go. They don't need anymore time. They need to be booted out as soon as possible.


Since Japan's experience with inept and incompetent government recently (over these past several years) has been a bad one, I think, then, we cannot expect a "better" government to come in to replace the current clowns we now have (see my comments above about the nature of government). Our best hope is for no government or deadlock within government.


At least, with a deadlock, the government cannot pass any new laws nor can they raise our taxes. 


Considering recent history (well the history of government since the beginning of time) that seems to be the best that we can hope for.

------------------

This article inspired by the guys from Sunset Drive (web page, blog & info here) who are holding a charity event for New Zealand Earthquake and Tohoku disaster victims on this Sunday June 5 at What the Dickens in Ebisu.

Sunset Drive

 Doors open at 5 pm. Entrance fee is ¥1,000 featuring Auctions, raffles, prizes and more fun. Performing that night will be Sunset Drive, icon girl pistols, Ruby Room Orchestra, Natccu and DJ's TIMUTAKU, goldifoxx, Abe Takayuki. Sunset Drive is really starting to happen in Japan. Check them out here.  

Fukushima Nuclear Power Risks and a Real World Example

Everyday, at the very top of this blog, you can see a link to what the daily radiation rates are in Tokyo and Tsukuba (75 miles north of Tokyo, towards Fukushima). The rates have fallen well within safe limits (actually hundreds of times within safe limits since the earthquake on March 11, 2011). 

Beach Boys - Don't Worry Baby

Nevertheless, I still get comments from people who mention nonsense along the lines of "background radiation levels are not the same as ingested radiation levels." Oh really? Thanks for all the Little Einstein's who have popped up recently and have become experts at radiation. No, ingested levels of radiation are not the same as background radiation levels. Absolutely correct.

That's why I do not show levels of radioactivity at the Fukushima power plant. I only show the levels in Tokyo and surrounding areas. I'm sure that if you are one of the few hundred people working at or in the plant for clean up then there is a danger. But I am not talking about the levels at Fukushima. I am talking about the levels in Tokyo. 

Tokyo is 230 kilometers away from Fukushima. No one in Tokyo is inhaling Plutonium... I'm sure there's lots of things people in Tokyo are inhaling, but Plutonium or other dangerous airborne radioactive particles are not some of them.

Once again, as I have written before, the issue comes down to facts and technology. Tabloid sensationalism that the mass media is giving the public is pure and simple nonsense.   

Why do people have such short memories? Don't people remember how the mass media said that Swine Flu was going to kill over 50 million people? As I wrote just 5 days into the nuclear accident in: Japan Nuclear Disaster Update & Strong Criticism of Western Media Sensationalism:

Actually, it astounds me that people do accept what what the media says as gospel truth. Don't forget that this is the very same media that told us 3 years ago that Swine Flu was going to kill more than 50 million people worldwide. This was the same media that told us that the USA had to invade Iraq because of Saddam's nooklar weapons. This was the same media that told us that SARS also was a killer virus that was going to wipe out entire populations. This was the same media that told us that Bird Flu was going to do the same.

As of today, worldwide  deaths from Swine Flu: 82. No nuclear weapons for Saddam (if he had any, do you really think we would have invaded Iraq?). Worldwide deaths from SARS: 100. Worldwidedeaths from Bird Flu: 80. Don't even get me started on Man Made Global Warming!

Fact of the matter is that this is the same media who constantly exaggerates stories in order to sell advertising space to an extremely gullible public. When will people ever learn? If history is any example then the answer is: Never. They'll never learn.

Just wait a year or three for the next killer disease and we can start all over again. 

I've stated it over and over; we live in a world of hype versus reality. You can choose which to believe. It seems that far too many wish to believe tabloid hype. 

Well, now, once again, a technlogy publication has come out with the facts to try to battle it out with those who are spouting off nonsense.

Today's recommended article comes from Boing Boing, one of the premiere technology publications in the world today. In this article, they break down the facts very simply. I'd like to quote it in full:

Japan nuclear crisis: A real-world example of radiation risks

Maggie Koerth-Baker

Last night, Xeni posted a link to this chart, showing radiation readings taken in all of Japan's different prefectures, except for Fukushima. I thought it might be useful to put this chart in context with what I've learned about radiation dosages and health from speaking with several health physicists over the last couple of days.

First off, a little bit of background. These measurements are coming from the Japanese government, and they're only showing what's going on at one place in each prefecture. It's entirely possible that other people, taking measurements at other locations, would get different numbers. Also, as you can see in the image above, this is showing change in radiation levels over the course of this Wednesday, Thursday, and Friday—March 16 through March 18. The measurements might have been higher or lower in the days preceding this sample, or in the days to come.

Disclaimers thus made, let's talk about what these charts show ...

The Basics

• Thanks to the magic of Google Translate, we can see that the measurements are taken in micrograys per hour. There are a lot of different units of measurement for radiation levels. I've been working mostly in either millisieverts or rems. So I'm going to convert this: 1 microgray = .001 millisievert

• So, now let's look at the prefecture with the highest spike in radiation levels. That would be Ibaraki Prefecture. If I'm understanding the chart correctly, the name in parenthesis tells you where, in general, the measurement was taken within the prefecture. So, in this case, the measurement comes from Mito, a city about 2.5 hours North and East of Tokyo.


On Wednesday, radiation levels at this one location in Mito spiked at .001 millisievert per hour (1 microgray), but didn't stay there for very long. Before Thursday, levels had fallen back to 0.00025 millisievert per hour, and they've mostly stayed about that level ever since—though it looks like the levels might be falling further today.

What The Doses Mean

• Let's look back at the dose and risk table put together for BoingBoing by the Mayo Clinic health physicist Kelly Classic. There's no entry for .001 millisievert on that table. The lowest it goes is .04 millisievert—the equivalent of a flight from New York to LA. It's a dose so small that it isn't associated with any increase in the lifetime risk of cancer.

• But time matters too, not just dose. This isn't just .001 millisievert, but .001 millisievertper hour. If you were exposed to that steadily, for 12.5 days, you'd end up with an actual dose of .3 millisievert—the equivalent of 30 days of natural background radiation, according to Kelly Classic's dose table. That's well above normal levels, but, again, even .3 millisieverts is still a dose that's so low, scientists can't find any evidence that it raises the lifetime risk of cancer.
More importantly, the radiation readings in Mito were only picking up .001 millisievert per hour for a short period of time. So, while that spike was big, it's unlikely to represent an equally significant increase in health risk.

• There's one final thing that matters here, though. Radiation levels in Mito started out at .00025 millisieverts an hour on Wednesday morning. That's where they fell back to after the spike. And they've been roughly around that same level ever since.

.00025 millisieverts an hour isn't normal. And that can start to add up.

There's 72 hours in three days. At .00025 millisieverts an hour, that gets you to a true dose of .018 millisieverts. Assume the spike lasted 3 hours, and that means the people of Mito have probably gotten close to .021 millisieverts over the last few days—about half the radiation exposure of a flight from New York to LA. The good news is that their overall risk is still low. To reach the point where your lifetime risk of cancer increases by 1%, you'd have to be exposed to 100 millisieverts. That could happen, if radiation keeps leaking out of Fukushima long enough, or if levels go up. But, so far, even though the dose is far higher than normal, the risk is lower than you might think.

Putting It All Together

• I think this is a really useful example, because it does a particularly good job of showing you how radiation dosages can add up for people living in the direct path of radioactive fallout—there's a reason why we're worried right now about the people who live in places like Mito. But it also demonstrates how fear can be larger than risk. This far from the nuclear power plant—Mito is three hours south of Fukushima—it would take a much larger output of radioactive materials and/or a much longer crisis to really put people at any noticeable risk. (Tokyo is easily 4.5 hours by car - traveling at 80 km per hour - south of Fukushima).


Right now, according to these numbers, the only people in serious danger are still the ones working inside the damaged power plant, and the only people with measurable risks are the ones who live very close nearby.


Here is a chart showing the radiation levels in Tokyo as of right now:

To see the comparison of levels starting March 1 (10 days before the accident) up to today, see here: http://ftp.jaist.ac.jp/pub/emergency/monitoring.tokyo-eiken.go.jp/monitoring/past_data.html .

The levels today are a about twice as high as they were on March 1, 2011. Which still makes Tokyo having a radiation level at about 1/4th that of the daily levels in Rome, Italy.

The facts speak for themselves. In spite of that, if you still want to panic, be my guest. It's doing nothing but ruining your mental health.