Posts from May 2013 (75)

Two hundred and sixty six years ago today, James Lind began what is regarded as the first proper controlled clinical trial

On the 20th May, 1747, I took twelve patients in the scurvy on board the Salisbury at sea. Their cases were as similar as I could have them. They all in general had putrid gums, the spots and lassitude, with weakness of their knees. They lay together in one place, being a proper apartment for the sick in the fore-hold; and had one diet in common to all, viz., water gruel sweetened with sugar in the morning; fresh mutton broth often times for dinner; at other times puddings, boiled biscuit with sugar etc.; and for supper barley, raisins, rice and currants, sago and wine, or the like. Two of these were ordered each a quart of cyder a day. Two others took twenty five gutts of elixir vitriol three times a day upon an empty stomach, using a gargle strongly acidulated with it for their mouths. Two others took two spoonfuls of vinegar three times a day upon an empty stomach, having their gruels and their other food well acidulated with it, as also the gargle for the mouth. Two of the worst patients, with the tendons in the ham rigid (a symptom none the rest had) were put under a course of sea water. Of this they drank half a pint every day and sometimes more or less as it operated by way of gentle physic. Two others had each two oranges and one lemon given them every day. These they eat with greediness at different times upon an empty stomach. They continued but six days under this course, having consumed the quantity that could be spared. The two remaining patients took the bigness of a nutmeg three times a day of an electuray recommended by an hospital surgeon made of garlic, mustard seed, rad. raphan., balsam of Peru and gum myrrh, using for common drink narley water well acidulated with tamarinds, by a decoction of wich, with the addition of cremor tartar, they were gently purged three or four times during the course.

The consequence was that the most sudden and visible good effects were perceived from the use of the oranges and lemons; one of those who had taken them being at the end of six days fit four duty. The spots were not indeed at that time quite off his body, nor his gums sound; but without any other medicine than a gargarism or elixir of vitriol he became quite healthy before we came into Plymouth, which was on the 16th June. The other was the best recovered of any in his condition, and being now deemed pretty well was appointed nurse to the rest of the sick …

Lind knew very little about scurvy apart from the typical progress of the disease, and he had no real idea of how the treatments might work.  That’s a handicap in coming up with ideas for treatment, but not in doing fair tests of whether treatments work.

The trial didn’t have an untreated group: all the patients got one of the treatments recommended by experts.  There’s no need for a controlled trial to have an untreated group — if there is an existing treatment, you want to compare to that treatment; if there is none, you may want to compare immediate vs delayed treatment.

Despite the dramatic success of fruit juice in the trial, it wasn’t adopted as a treatment. That, sadly, can still be the case today.  New drugs or surgical techniques are taken up enthusiastically, but boring interventions like nurse home visits or surgery checklists get less attention. Still, things are much better than they were even twenty years ago. Nearly all of medicine accepts the idea of randomized controlled comparison, and it is spreading to other areas such as development economics.

There are two excellent, free books about clinical trials and health choices: Testing Treatments, from the James Lind Initiative, and Smart Health Choices, from Les Irwig (at Sydney Uni) and coworkers.

Much of clinical trials development is unapologetically technical, but there are important areas where public participation can help:

• The James Lind Alliance asks patients and clinicians to say what questions matter most.  Clinical trials still tend to answer questions that are scientifically interesting or commercially important, not what actually matters most to patients
• The Cochrane Collaboration is attempting to collect and summarise all randomized trials.  The Cochrane Consumers Network is for non-specialist participation — in particular as Consumer Referees to help ensure that summaries of research address the questions that are important to consumers and are presented in language that consumers can understand.
• Ethics Committees that review clinical trials and other human research in New Zealand are required to have non-specialist community members. This is a substantial commitment, but one that is important if ethics committees are to be more than just red tape.
• And if you haven’t yet signed the AllTrials petition, calling for the results of all clinical trials to be published so we can know what treatments work, now would be an excellent time.

From the University of San Francisco. The winners were all interactive maps, showing, respectively: pollution, population change, and child mortality.

Surprisingly addictive

• Color: match colours under a time limit
• Munsell Hue Test: arrange colours in order between two endpoints.

From the Wellcome Trust Monitor, a survey examining knowledge and attitudes related to biomedical science in the UK

The survey found a high level of interest in medical research among the public – more than seven in ten adults (75 per cent) and nearly six out of ten of young people (58 per cent). Despite this, understanding of how research is conducted is not deep – and levels of understanding have fallen since 2009. While most adults (67 per cent) and half of all young people (50 per cent) recognise the concept of a controlled experiment in science, most cannot articulate why this process is effective.

Two-thirds of the adults that were questioned trusted medical practitioners and university scientists to give them accurate information about medical research. This fell to just over one in ten (12 per cent) for government departments and ministers. Journalists scored lowest on trustworthiness — only 8 per cent of adults trusted them to give accurate information about medical research, although this was an improvement on the 2009 figure of 4 per cent.

This is a common question from our students. Unfortunately our perspective does not always lend itself easily to life outside of research and academia, as what I look for in a curriculum vitae and in a job interview is usually with respect to hiring someone who will become an academic staff member. However, fellow statistician, and the Young Statisticians representative for the New Zealand Statistical Association executive committee, Kylie Maxwell has posted her own experience as part of the International Year of Statistics.

Keith Ng’s budget visualisation now has today’s newly-released Government budget.

(update) There’s also one at Stuff, by Harkanwal Singh (note that it uses nominal, not inflation-adjusted amounts)

Here is a site to show with a flourish when your friends tell you at the pub that studying Statistics is no use. LifeHacker reports that BeerViz attempts to use historical data collected by BeerAdvocate, and presumably a statistical model, to suggest new beers to you based on what you already like. If they’re not using a statistical model then there is a great challenge for you loyal readers!

A report by research firm Strategy Analytics has estimated that Korean electronics giant Samsung took a whopping 94.7% share of the $US5.3 billion first quarter operating profits for Android handset sales. Whichever way you look at it, currently Samsung is the Android platform of choice.

The Register notes that the same report notes that Android has 43% of the smartphone market share.

• Via @felixsalmon, bad graphics moving into baseball

• Twitter Hate Map aims to show where racist or homophobic tweets occur.  It tries to correct for the usual denominator problem, but there just aren’t enough tweets from some parts of the country

• Early this morning, the moderately accurate pageview counter on WordPress ticked over to quarter of a million page views on StatsChat.  It’s only a small milestone — someone like Ben Goldacre gets more hits than that every time he tweets — but at least we’re world famous in New Zealand. Web metrics site Alexa.com estimates that 0.000066% of internet users have seen StatsChat!

Rafa Irizarry at Simply Statistics has a longish piece on the future of applied statistics:

Despite having expertise only in music, and a thesis that required a CD player to hear the data, fitted models and residuals , I was hired by the Department of Biostatistics at Johns Hopkins School of Public Health. Later I realized what was probably obvious to the School’s leadership: that regardless of the subject matter of my thesis, my time series expertise could be applied to several public health applications. The public health and biomedical challenges surrounding me were simply too hard to resist and my new department knew this. It was inevitable that I would quickly turn into an applied Biostatistician.

It makes a nice change from the people worrying that computer science will beat us up and steal our lunch.