Capacity Planning

At Ask! restaurant in Durham, where we went on Saturday night with friends, the toilets are more discreet than most.
There are individual cubicles: perfect for  capacity planning. This means that, if you think that women will require more cubicles than men, you can allocate more cubicles to women. And they have done exactly this, four allocated women versus two allocated to men.
The reason Why?
There may be lots of reasons why they've decided to provide individual cubicles instead of restrooms; studying toilets is not my favourite activity. But it reminded me how important it is to match your resources (your capacity) to meet your demand.
Too much capacity for the actual demand: the service costs too much, and resources are diverted from some other vital service. If you are a commercial entity, your profitability will suffer. If you are a service for public good, you find yourself unable to provide some other service needed by the community.
Too little capacity: queues develop. Again, if you are commercial, you may lose customers; if you're a service for public good, you may be fined or severely criticised.
A dark art
But capacity planning is something of a dark art. In just about every situation I have worked for public good, the numbers have been relatively small; numbers on the list for surgery (12 lists but effectively 12 queues because it’s difficult to transfer patients between lists on the day); numbers of calls coming in somewhere between 1 and 30 of 45 per hour (reform of urgent care services in London) for example; 2.5 full-time equivalent GPs in the GP practice;.
It only takes one member of staff either way
Getting the planning wrong by one member of staff either way can have a dramatic impact on effectiveness. I've used a Poisson binomial distribution which dramatically demonstrates the benefits of scale; I've used Excel spreadsheets, and I've used the care planning system (CPS) designed by Simon Dodd. When the numbers from different systems converge, you probably have the right answer.
The Commissioner Provider split.
For providers, the benefits are obvious: the surplus of income earners costs allows investment in new ways of doing things, and better service in other areas.
But why is this relevant to the commissioner? We've noticed over the last few years the provider hospitals have an uncanny ability to work round demand management; wherever the commission has put their focus, activity booms in another place. It isn't clear why this is happening, but with payments to acute trusts rising faster than the increase in income to commissioners, and commissioners' income coming to a standstill, it matters! It's the same in social care; the providers have a lot more independence, a lot more autonomy, but the tensions to match supply to demand may be even more acute; and the commissioner can often help.
Second-guessing your provider, and understanding how they work, is important. And now, with the new contracts being written (2010/11 templates now available from the DH website) is the time to look more closely.
It's the right time to take action
We all recognise that resources are limited. We do the best we can with what we have. I believe I can help with the scientific approach, based on my experience in all of these areas. Please feel free to contact me.