SadButMadLad's Blog

Just another blog complaining about anything and everything

Posts Tagged ‘bad science

Spray of death from the windscreen

The latest health scare news is out today. Its that you can catch legionnaire’s disease from the windscreen wash in cars. The explanation being that the windscreen wash water is a nice warm temperature next to the engine and that it is stagnant. However when you look into the figures it’s another scare which has no foundations.

The scare says that if you catch legionnaire it is 20% likely to have come from a windscreen wash bottle and that 10% of such infected people die. This sounds like a extremely high risk and gives the impression that everyone MUST start adding windscreen cleaner with extra anti-bacterial products to the water in their wash bottles otherwise people will start dropping like flies on the motorways.

In fact the chance of catching legionnaire’s disease is miniscule. There were 345 cases last year in the UK. Out of a population of say 60m, thats a 0.0000575% chance of getting it. Out of the 345 cases, about 30 died. So an even smaller chance of dying. Those with medical problems are more likely to die than healthy people who’s symptoms are spotted early. Out of the 345 cases about 70 probably caught the disease through driving.

And even then its only a theory. They haven’t actually tested washer bottles for legionnaire’s disease. They are only theorising that it is the cause because a number of people who caught the disease are drivers. They says these drivers are professionals, such as bus drivers and truck drivers. But many people drive. Salesman drive. Are they profressional drivers too? People commute to work, are they classified as professional drivers. Sometimes they drive more than bus drivers.

A classic case of lets make a news story out of nothing to get some publicity for our organisation. If it makes people more scared of the world, then all the better because we can then sell them more pills.

Finally, just to make sure you understand basic scientific principles…..

Correlation does not imply causation

It seems that the figures in the study are only for the South West of England and not for the whole of England and Wales. The figures from the study are 164 cases in 2009, where 22 where from outbreaks which leaves 142 where the disease was aquired in the commuity of which 28 might have been prevented.

Written by sbml

June 14, 2010 at 12:23