Posts filed under General (3156)

I’ve been following with interest the British Medical Journal‘s bold new move to refuse to publish research on drugs unless the clinical trial data is made available for independent analysis from January 2013. This is great news for other researchers, scientists and statisticians wanting to independently analyse and verify findings from studies.

In an editorial, the journal says they want to “leverage their power and publish only where there is a commitment to make the relevant anonymised patient level data available on reasonable request.” Further, they are campaigning for open data using Tamiflu as an important case study after being frustrated with years of trying to get drug company Roche to fulfill its promise to release full clinical trial results.

The BMJ quotes Ben Goldacre’s new book Bad Pharma:

“Drug companies around the world have produced some of the most amazing innovations of the past fifty years, saving lives on an epic scale. But that does not allow them to hide data, mislead doctors, and harm patients.”

Goldacre is one of a group of campaigners in the UK currently pushing the government to legislate for true transparency regarding clinical trials.

Watch a recent TED video from Ben Goldacre on the other “scandalous” problem of unreported trials of negative or inconclusive drug trial findings:

I believe Media Watch will be covering this story this weekend too.

Ben’s blog, Bad Science is always excellent reading, and I am looking forward to reading his newest book and hope that the BMJ’s campaign is successful.

Another random note on the US elections: the Congressional districts have been redrawn after the 2010 Census. In most states, this is done by the incumbent state government.   In a perfect world, the possible electoral advantages wouldn’t affect the boundaries.  As an example, look at the Pennsylvania map (especially districts 7 and 12)

Article II, Section 16 of the Pennsylvania Constitution says that the Commonwealth’s 50 senatorial districts and 203 representative districts “shall be composed of compact and contiguous territory as nearly equal in population as practicable.” It also says that “Unless absolutely necessary, no county, city, incorporated town, borough township or ward shall be divided in forming either a senatorial or representative district.”   

• Stuff has a story about real estate that goes beyond nominal prices and has meaningful comparisons with the past (based on ratios to average household disposable income)
• If you want somewhere to obsessively follow the US election, there’s live blogging at fivethirtyeight.com
• The Washington Post looks at Google trends for the query “who is running for president?”
• Stuff has a story about studies of multivitamins, reporting that they didn’t find the health benefits they were looking for, and then concluding “The bottom line: Dietary supplements have varied effects, and whether one is right for you may depend on your personal health profile, diet and lifestyle.” You could have said that (more convincingly) without the research

That’s lead, Pb, the element. The Herald has a headline “Dangerous lead levels in Aussie kids – experts”. The article says

Health experts are calling for new national guidelines amid fears that up to 100,000 young Australian children could have dangerously high levels of lead in their blood.

The new proposed law for ‘natural remedies’ will provide some limits on health claims: they must be supported by scientific evidence or traditional evidence.  It’s depressing that this has to be considered an improvement over the current situation.  It’s also unfortunate that there is a special exemption for the largest category of health claims that have support neither from tradition nor science: homeopathic remedies (invented in 1796).

If ‘traditional’ evidence required a tradition of use of the product in essentially the form being sold and for essentially the indication being marketed, I wouldn’t object.  So, for example, it’s reasonable to say that ginger has been used traditionally in China to stop coughing, because it has. Many people would consider this sufficient reason to buy and use ginger for coughs, and I don’t see why there’s a vital national interest in deterring them.  What should be stopped is the ability to claim that a treatment is known to work simply because it has been traditionally used, and the ability to make up new ‘traditional’ uses for marketing convenience.

In the end, the impact of the law will depend on regulations and enforcement, not on statute.

Requiring ‘scientific evidence’ won’t get us very far without standards for the level of evidence required.  As StatsChat readers know, a huge variety of plant extracts have been shown to kill cancer cells in test tubes, or affect biochemical measurements in cell cultures. Newspapers are willing to take this as sufficient basis for stories and headlines claiming ‘can prevent cancer’ or ‘is helpful in treating diabetes’. If the proposed Authority takes a similar view, almost anything will be allowed.

Enforcement is also critical.  In theory, the US requires vendors to have scientific evidence for claimed health effects of natural remedies, but in practice they can get away with almost anything, because the FDA doesn’t have the resources for enforcement and there’s no practical way for private citizens to act. At the moment, the NZ Advertising Standards Authority has the ability to remove ads making health claims for which the vendor cannot supply evidence, and they have the willingness to act on public complaints from anyone who is unhappy about misleading health claims. The new law’s requirement for prior notification of health claims could strengthen enforcement, or weaken it, depending on how the requirement for evidence is interpreted.

Frances Woolley at Worthwhile Canadian Initiative has another fascinating graph.  This one’s based on US data from the World Values Survey, where people were asked which income decile they are in:

As she describes, it doesn’t seem to be that the survey has accidentally undersampled the poor and the rich.  People seem to be deluded about where their income fits in the national distribution.

There are a number of possible explanations.  At the high end, there is the fact that people with more money than you are more visible, so it’s easy to overestimate how many of them there are.  At the low end, part of the explanation may be that young people whose family income has been higher in the past and will be higher in the future place themselves higher up in the distribution. The obvious example is university students, who in some ways behave more like their parents than like non-students with similar household income.

Part of it, though, is that people just overestimate how normal they are, just as  you (and I) probably overestimate how many people care about statistics in the media.

For those of you who have been living in a cave on Mars with your eyes closed and your fingers in your ears, the US is having a presidential election.

Nate Silver, a former baseball nerd who has climbed to fame by computing averages of opinion polls, said earlier this week that  Obama had a 72% chance of winning.  Old-fashioned political pundits disagreed, saying the race was too close to call (they also accuse Silver of just computing averages of opinion polls).

Andrew Gelman, a stats professor at Columbia University, has an opinion piece in the New York Times explaining what 72% means:

What I’m saying is that I can simultaneously (a) accept that Obama has a 72 percent chance of winning and (b) say the election is too close to call. What if the weatherman told you there was a 30 percent chance of rain — would you be shocked if it rained that day? No.

For Kiwi readers, a useful analogy might be rugby.  The All Blacks have beaten Australia in 70% of their games overall, and 75% in NZ.

Surveys really are the best way to get free advertising space.

Speight’s did some sort of survey of Kiwi men, and it’s turning up all over the place. They asked 504 men some incompletely described set of questions with no hint as to how they were selected.

Highlights of the results:

• A staggering 97% claim they would pay the correct amount of money when buying from an honesty box.  We can conclude that men who are financially dishonest also lie on surveys.
• Just over 80 per cent said they would help a stranded motorist on the road, but in Otago only 76 per cent said they would stop to lend a hand.  If there are 504 respondents across the country, you might wonder if there are enough in any one region to distinguish 76% from 80%.  No way.

The press release quotes Anna Gestro from Speight’s as saying  “The Speight’s survey is a small insight into the Kiwi male psyche.” 

How small? Very, very small.

Despite all the media coverage of Hurricane Sandy, I found it hard to get a sense of the scale of the storm and the destruction it caused – there’s plenty of noise, but hard to find the signals.

A few sources of information I’ve found useful are:

A map in yesterday’s NZ Herald giving useful size context to the storm:

The New York Times is real-time graphing and mapping the number of customers affected by power outages in New York city after Hurricane Sandy:

For another good overview divided by different types of damage in New York city, see: Assessing the Damage From Hurricane Sandy.

Google has an interactive crisis map.

There were not-so-useful statistics being used such as “Facebook Sees Mentions of ‘Hurricane Sandy’ Spike 1 Million Percent”.

The Atlantic does a nice job of verifying social media photos of Sandy.

Have you found any good resources online for getting a sense of the scale and destruction of Hurricane Sandy? Let me know!

According to Stuff, a Japanese research study has found that sugary drinks cause strokes. In women, not men (they found a weak association in the opposite direction in men).  And only strokes, not heart disease. And when they say “sugary”, this isn’t based on the sugar content, since 100% fruit juices were excluded.   The researchers have some fairly unconvincing excuses for why only strokes were increased, and only in men.

The headline was “Female? Put down the fizzy drinks”, which manages to capture the implausible part of the findings while getting the plausible part completely wrong: the research looked at drinks with added sugar, not drinks with added fizz.

The story does better than the headline, at least putting the research in context with the other findings that suggest the impact isn’t restricted to strokes in women. They also quoted an expert from the Cleveland Clinic, who sensibly ignored most of the details of the study findings and said:

”It makes sense, if (sugar sweetened beverages) increase the risk for obesity, diabetes, insulin resistance, inflammation, then it should, in fact, raise the risk for cardiovascular disease, and that’s what we’re seeing,” said Adam Bernstein, a researcher at the Cleveland Clinic, who was not involved with the study.

Other sources did far worse than Stuff. For example, the site Food Navigator completely misrepresented the results, saying that “one fizzy soft drink per day could bump up the risk of stroke by up to 80%”, when the actual figure in the abstract is 21% for total stroke (something that they got right later in their story). They also said the risk was increased in men, which is the opposite of what the paper says, and that the participants were all between 40 and 49, when in fact they were between 40 and 59 at the start of the study and between 58 and 77 at the end of the study.

The really interesting question is why this study, which doesn’t actually add much to what we already know, has made global news.  We’d have to ask Reuters about that.