Drink-driving figures questionable

I HAVE long since abandoned any hope that the self-serving information which is regularly published by the Northumbria Safety Camera Partnership would be subject to any proper challenge by the bodies asked to fund that (and similar bodies) which exist now only, it seems, to provide employment for a considerable number of administrators, through the collection of fines based upon the strategic siting of enforcement cameras throughout the force area.

Now, however, it appears that the erroneous and partial interpretation of randomly selected data can be used to support any proposition in the arena of driving with excess alcohol in the body.

The recent story ‘Less drink driving this December’ (News Guardian, January 27) carried the statistic issued by Northumbria Police which claims to support the ‘message’ that ‘an increasing majority of people who were stopped were heeding the drink drive message’.

We are told that the reduction in the number of positive tests from 94 (December 2009) to 88 (December 2010) represented a ‘decrease of three per cent’.

In fact in nominal terms it was a reduction of 6.4 per cent.

What would have been more illuminating and a cause for some thought is the fact that the number of positive tests in December 2009 – 94 – represented 9.4 per cent of all tests conducted whereas in 2010, the number of positive tests – 88 – in a sample of 1,383 (37 per cent higher than last year), was only 6.4 per cent, a reduction of 31 per cent in a much larger test sample.

I could also represent the rate of positive tests in 2009 as being almost 50 per cent higher than in 2010.

Of course the true reasons for the differentials in the results between the two years will be complex and probably unknown even to the police.

Given the vagaries of the weather, the numbers of working days or weekend days in the sample periods as well as the time available to officers to devote to the testing of drivers means, in my opinion, that the ‘improvements’ claimed are questionable and unproven.


Alma Place North Shields