An annoying trope in US political stories (which, fortunately, hasn’t made it here yet) is to criticise a politician for using too many first person singular pronouns — saying “I” and “me” too often.  These stories often get analysed by the computational linguists over on Language Log, who tiredly point out that the claim is (a) largely irrelevant to the point being made, and (b) false.

This week’s example is the speech by New Jersey Governor Chris Cristie at the Republican National Convention.  A New York Times piece said

Gov. Chris Christie is getting rave reviews today for his performance at the National Republican Convention, and there’s no doubt in my mind that he did a huge amount of good for the three most important people in his life – he, himself, and him….

By my count, Mr. Christie used the word “Romney” six times in his address. He used the word “I” 30 times, plus a couple of “me’s” and “my’s” tossed in for seasoning.

but as Mark Liberman points out, the actual use of first person singular pronouns was slightly lower than in the speeches by Paul Ryan, Anne Romney, Rick Santorum, Mike Huckabee, and much lower than Clint Eastwood.  It’s also slightly lower than in the similar speech by (then Illinois Senator) Barack Obama at the 2004 Democratic Convention.

Since newspapers almost exclusively cover positive results in medical research, it’s easy to have an unrealistically optimistic view of progress.  Most weeks, there are multiple stories about some new compound or extract that kills cancer cells in the lab, but we don’t learn what happens later.  And no, these treatments aren’t suppressed by evil multinational drug companies, who are actually in desperate need of new things to sell us.  As a partial corrective, here are some relatively recent research findings that make it less likely we’ll soon get new treatments for important diseases.

Alzheimer’s:  trials of two antibodies against amyloid plaques, which had shown promise in mice, failed to  show benefits in patients (one was robustly null, the other was borderline and the company hasn’t quite given up hope).  Inhibiting one of the enzymes that makes amyloid has also failed.

Heart disease:  Raising ‘good’ HDL cholesterol was a big hope, but three separate approaches to treatment have so far failed to provide any convincing benefit in clinical trials, and genetic studies suggest that although HDL is associated with lower risk, it may not actually be responsible for the reduction.

 Diabetes:  drugs to reduce insulin resistance through a new target called PPAR were going to be the new revoluation.  Troglitazone and rosiglitazone (Avandia) got into use but turned out not to actually reduce complications of diabetes, several others didn’t make it past clinical trials.  An even more promising approach was to inhibit one of the transporter proteins in the kidney, and dump all the excess glucose in urine. It didn’t work either.

One piece of good news as balance: a very promising new antibiotic for tuberculosis has succeeded in a phase II trial of drug-resistant TB.  The trial looked at how fast patients became non-contagious, and the new antibiotic got more patients to that state, faster.  The next step, just about to start, is a longer trial to see if patients are actually cured — it could still fail, of course.

One of the problems in medical research, exacerbated by the new ability to measure millions of genetic variables at once, is that you can always divide people into sensible subgroups.

If your treatment doesn’t work, or your hated junk food isn’t related to cancer, overall, you can see if the relationship is there in men or in women.  Or in younger or older people.  Or in Portugese-speaking bassoonists. The more you chop up the data, the more likely you are to find some group where there’s a difference.  You can then focus on that group in your results.

To combat this tendency, my Seattle colleague Noel Weiss has been promoting the slogan “conclusions of difference require evidence of difference”.  That is, if you want to report that cupcakes cause cancer in men but not in women, you need evidence that the relationship is different in men and in women.  Finding supportive evidence in men but not finding it in women isn’t enough: that’s not evidence of a difference.  Needing evidence of a difference is especially important when you wouldn’t expect a difference.  We expect most things to have basically similar effects in men and women, and where the effects are different there’s usually an obvious reason.

All this is leading up to a story in the Herald, where a group of genetics researchers claim that a well-studied variant in a gene called monoamine oxidase increases happiness in women, but not in men.  We know this is surprising, because the researcher said so — they were expecting a decrease in happiness, and they don’t seem to have been expecting a male:female difference.  The researchers say that the difference could be because of testosterone — and of course it could be, but they don’t present any evidence at all that it is.

Anyway, as you will be expecting by now, I found the paper (the Herald gets points for giving the journal name), and it is possible to do a simple test for differences in `happiness’ effect between men and women. And there isn’t much evidence for a difference. For people who collect p-values: about 0.09 (Bayesian would get a similar conclusion after a lot more work). So, if we didn’t expect a benefit in  women and no difference in men, the data don’t give us much encouragement for believing that.

Testing for differences isn’t the ideal solution — even better would be to fit a model that allows for a smooth variation between constant effect and separate effect — but testing for differences is a good precursor to putting out a press release about differences and trying for headlines all over the world. We can’t expect newspapers to weed this sort of thing out if scientists are encouraging it via press releases.

Team Ratings for Round 26

Here are the team ratings prior to Round 26, along with the ratings at the start of the season. I have created a brief description of the method I use for predicting rugby games. Go to my Department home page to see this.

Performance So Far

So far there have been 184 matches played, 108 of which were correctly predicted, a success rate of 58.7%.

Here are the predictions for last week’s games.

Predictions for Round 26

Here are the predictions for Round 26

Last Wednesday I wrote that a survey should always provoke the questions “How was it done? By whom? and What are they selling?”

This week, Stuff and TVNZ tell us that half of New Zealanders don’t have a will, and that there are more wills in the South Island than the North Island.  This survey was commissioned by Public Trust (who do wills), but there’s no information about how the survey was done or by whom.  Public Trust don’t currently have any information on their ‘News‘ webpage.

An interesting coincidence, but probably no more: at the moment, the proportion saying they have a will on the clicky poll on the Stuff website is 47%.

Stuff has an example of the recurring problem of an perfectly good medical science story spoiled by not one, but two appalling headlines.

Currently, on the ‘Wellbeing’ section of the website you see

Feeling poorly? Try Vegemite

and on clicking through to the story

Vegemite may ward off superbugs

The story then goes on to say that high concentrations of niacin, a vitamin found in many foods, including, yes, Vegemite, has been found in test-tube and mouse studies to help in killing bacteria.  It then says

The Internets are full of a story about herbal tea curing breast cancer. The Herald is actually more restrained than many:

An extract commonly found in herbal tea can stop the spread of breast cancer, researchers have found.

That isn’t what the researchers found.  For a start, unless you’re in or near Pakistan, the extract isn’t commonly found in herbal tea.  But that’s not the main problem.

This blog has a tendency to look pro-drug and pro-alcohol, because we react to media stories and these topics are currently popular for exaggeration and over-interpretation.  It’s a nice change to find some serious anti-drug research that the media are reporting pretty sensibly. (Otago Daily Times, Stuff, Herald, 3News, TVNZ)

Researchers in Dunedin, and their international collaborators, used data from the Dunedin Study, which recruited about 1000 babies born in a Dunedin hospital in the 12 months starting April 1972.  These babies, now adults, have given a lot of data up to medical science. In particular, they had a range of neuropsychological tests at age 13 and then again at age 38, and they were interviewed about cannabis use.   The headline results were about IQ, but the study looked at a relatively broad range of cognitive function tests, and also at self-reported problems with memory and attention.   Participants who smoked cannabis as teens had broadly worse cognitive function, by a margin that’s large enough to be a concern.  This didn’t show up in people who started smoking cannabis as adults.  The paper is in PNAS; the abstract is free.

What’s most distinctive about this study is the before-after comparisons.  You often see (and we have pointed out) studies that claim to have found “changes” when they only had one time point, and so really only looked at “differences”.  The Dunedin Study has changes from before cannabis use to after cannabis use.   Also, since the participants are the same age and all from Dunedin, they are less heterogeneous in many ways than participants in other research studies.

The differences in IQ are within the range of the Flynn effect, so it’s still possible that this is a social effect rather than a biochemical one, or that it’s caused by pre-existing differences in people’s interest in the sort of activities that increase IQ test scores, or something.  Better data, however, will be extremely difficult to collect, and treating these results as probably true seems sensible.  Presumably the adverse effects would also be found with synthetic cannabimimetics, but these are too recent for there to be data, and they have other problems not present with cannabis, such as the risk of acute overdose.

A number of the stories quote Ross Bell, of the Drug Foundation, being sensible:

Simply banning drugs such as cannabis and then thinking that was the problem solved would not work, Mr Bell said. “What we’re lacking in New Zealand is support for widespread, high-quality, well-constructed prevention messages targeted at younger people.”

Congratulations to Alan Keegan for nominating* us (!) for a bad graph. Thomas has posted about it here. Congrats Alan!

(* nomination was for the correct time period, but added to the previous week’s nominations page.)

Three sentences from a Herald story 

The Ministry of Transport study used blood samples taken from 453 drivers who caused crashes.

Of that group, 156 were found to be on drugs not administered by a medical professional

Drivers with more than the legal limit of alcohol in their system made up just over half of the 453 samples analysed.

Now try to fill in the blank  in the headline “Tests reveal most crash drivers                                “

If you said “were drunk”, your arithmetic is better than your sense of headlineworthiness, not a problem the Herald had.