Last week a clean, near perfect trial. This week research conducted in the chaotic world of a cholera outbreak. But this is important stuff - as the authors say, we need to know what happens under field conditions. The basic method is simple - a case control study, comparing the vaccination history of cases (patients with cholera) versus controls (people without cholera). But in field conditions it's not so easy to tell whether people actually have cholera or not, and whether they've been vaccinated or not. So there are various extra study elements built in to cope with that.
I hugely enjoyed reading this account of research from the Bristol team. It's not exactly a spoiler to say that the end result was negative, because that's clear from the abstract. But enjoy the beauty of the research - they seem to have thought of everything.
What can we take away from this?
Firstly, one really good study tells us more than 100 poor ones. All those poor studies have gone into systematic reviews but with meta analysis as with much else - garbage in, garbage out. The biggest problem is so much parental (or self) report of activity. Objective measurement of activity with accelerometers must now be mandatory for this type of research.
Secondly, it's difficult to teach a way of life in schools. I'd be interested to know whether kids are more active in, say, Denver than in Bristol. I have a friend who lived in Denver and he remarked on what an outdoorsy place it was - getting out and about was the way of life there. I liked the comment in the paper that kids shouldn't have to think about whether or not they are enjoying an activity.
Let's face it - a heatwave in the UK isn't really a heatwave. Not if you've been to the Mediterranean, or Australia, or Africa, or USA or practically anywhere else on earth. The Gulf stream does its stuff in moderating our climate.
But the government is touchy about accusations of neglecting the vulnerable so even in England a heatwave plan must be produced. Here it is. Maybe the mildness of our climate means we don't respond properly when temperatures push up beyond 300C. We don't do things which seem obvious in really hot countries - sunshades in places where people will queue, air conditioning in the Underground and so on.
One feature to note is the use of alert levels, with predefined thresholds and actions to take at each level. There's a lot of common sense (have a cold drink) and one or two evidence based recommendations (don't point a fan directly at a frail old person).