There will be important differences between clinical commissioning groups (CCGs) and primary care trusts (PCTs) – it could hardly be otherwise, given the radically different context in which CCGs will be operating. But in terms of the population size they cover – a hugely significant issue for any commissioning body – CCGs and PCTs look increasingly similar.
We have known for some weeks now that the average size of CCGs looks set to be considerably larger than originally anticipated – the median population covered by the 212 CCGs preparing for authorisation is 226,000, compared to 284,000 for the 151 PCTs they replace.
But many have assumed that while the average size of CCGs may not be so different, one thing that will be different is the degree of variation. The analysis below shows that this is not the case.
There is certainly significant variation between CCGs – with a 13-fold difference between the biggest and the smallest. But what is often missed is that the same is true with PCTs – Hampshire PCT covers a population 14 times larger than Hartlepool PCT.
The graphs below illustrate this similarity. In the first, each line represents one PCT or CCG (figure one). In the second, the horizontal axis has been standardised to allow direct comparison (figure two). What these figures show is that the distribution of CCG sizes – though not exactly the same – is not as dissimilar from PCTs as we may have thought.
Figure one: Comparison of CCG and PCT population size (raw data)
Figure two: Comparison of CCG and PCT population size (standardised)
There are, however, some important caveats to bear in mind
First, management resources will be lower for CCGs, and as a result of this more of their functions will be shared between CCGs or delegated to commissioning support services and other organisations. So the organisations themselves will be smaller than PCTs even if the population size they cover is comparable. In some cases the extent of sharing or delegation of commissioning functions may raise the question of whether the size of each individual CCG is the most important issue.
Second, while the degree of variability may be similar for CCGs and PCTs, the factors driving it could be very different. PCTs are administrative constructs, whereas the shape and size of CCGs has been influenced by a number of factors, including clinical flows, perceived ‘natural’ population groups, the pattern of professional relationships across a local area, and existing administrative boundaries. A CCG may be small (or large) for different reasons than those that determine PCT size.
The analysis shown here does not imply that the way CCGs function or the outcomes they achieve will be comparable to PCTs – that remains to be seen. What it does illustrate is how pragmatic considerations can shape the implementation of policy and take it in very different directions from those originally envisaged.