Why Zack Cooper is Wrong

As the Lords begin scrutiny of the Health Bill we will again hear the claims that competition improves healthcare.  The work of Zack Cooper will be cited yet again as THE definitive study.  But it is simply wrong; here’s why.

The introduction of competition into the NHS in 2006 when choice was offered of elective provider clearly had effects as acute providers adjusted to the new system.  The claim is that the impact of the changes in organisations which felt the threat of competition led to improvements in the quality of clinical outcomes when compared with others not subject to competition.  The evidence is that in those trusts subject to competition there was a significant improvement in the outcomes for patients that experienced a heart attack, compared with other trusts not subject to(or less subject to)  competitive forces.

If the claims are true then they apply across the whole system.  If the introduction of choice and competition somehow (the how is not explained) improved outcomes then the evidence must be everywhere.

My test used the excellent data set from the East of England Health Observatory for in hospital mortality aggregated across the Region, but also available for each acute trust.  If Cooper is right then there will be a significant improvement in mortality when you compare the pre 2006 data with post.  There isn’t.

The number of in hospital deaths is not something subject to coding error or interpretation, and at the level of a whole region a system wide impact would have to be clear.

Those with far better statistical skills can look at this data, or for another Region or even for the whole country.  They can smooth the data, adjust it for population or activity growth but the results will be the same – anyway it is not hard to do.

If the introduction of competition led to improvements in clinical care and outcomes then this must translate into acceleration in the established rate of improvement in the number of deaths or the mortality rates across the system. It did not.

Irwin Brown

Socialist Health Association

October 2011