What should you do if you have a large and growing waiting list backlog, and no way to clear it?

You could devote as much capacity as possible to treating the longest-waiting patients. That would keep maximum waiting times as short as possible, and keep to the principle that patients of similar clinical priority should be treated in turn. Unfortunately, admitting so many long-waiters would also fail the 18-week target: that 90 per cent of admitted patients must have waited less than 18 weeks. For this, you could be fined up to 5 per cent of your elective care revenue by your commissioners.

What’s the alternative? You could choose to achieve the target regardless. That means you could only devote up to 10 per cent of your capacity to the longest-waiting patients. The number of long-waiting patients would grow inexorably, but because you would be achieving the admission-based target you would not be fined.

When faced with this choice, different Trusts go different ways. Here is a scattergram for Ophthalmology (it’s a similar picture in other specialties too). The chart shows the time within which 90 per cent of patients are admitted (vertical axis) plotted against the time within which 90 per cent of patients are still waiting (horizontal axis). (Data is for December 2010 from Department of Health.)

The rump of Trusts are nestled in the desirable quarter of the 18-week gridlines. But some aren’t, and two of them are picked out in different colours: Royal Berkshire NHS Foundation Trust (in red), and Western Sussex Hospitals NHS Trust (in green). I’ve chosen them because they illustrate the two options quite well.

The next link is a drilldown into Royal Berkshire’s data. They are comfortably achieving the admission-based 18 week target. But since mid-2009 the waiting list has been growing inexorably, with 68 per cent of incomplete pathways (i.e. patients still waiting) over 18 weeks. Nevertheless, the Trust has (almost) consistently met the 18-week target by not admitting long-waiters in significant numbers. This is not a criticism of the Royal Berkshire; they have been under massive pressure to do this. But it is an indictment of the admission-based 18-weeks target.

Royal Berkshire NHS Foundation Trust: Ophthalmology

And here is a drilldown into Western Sussex’s data. Their waiting times have also grown since mid-2009, and an even higher proportion of their incomplete pathways (75 per cent) are already over 18 weeks. But this Trust has devoted a lot of capacity to treating those long-waiting patients, so that few are waiting longer than 30 weeks. Unfortunately their efforts to treat long-waiters mean they look very bad against the admission-based target, achieving only 53 per cent of admissions within 18 weeks. This puts them at risk of maximum fines from their commissioners, even though they are doing the right thing for their patients.

Western Sussex Hospitals NHS Trust: Ophthalmology

The admission-based 18-week target is clearly a problem when waiting lists grow. It deters hospitals from treating their long-waiting patients; it violates the principle that patients with similar clinical priority should be treated in turn; and it misleads the public with statistics that make everything look rosy.

The solution, I suggest, is to change the target from “90 per cent of admissions within 18 weeks” to “90 per cent of incomplete pathways within 18 weeks” (i.e. 90 per cent of those still waiting, at any point in time, should not have waited longer than 18 weeks). Now that central enforcement of the target has ceased, this could be negotiated locally between commissioners and providers.

It would mean tackling the underlying issue, of course, and that would be expensive at Trusts like the Royal Berkshire and Western Sussex. But isn’t tackling the underlying issues and improving outcomes for patients meant to be what the reformed, clinician-led NHS is all about?