The commitment that patients should wait no more than 18 weeks for planned care is one of the English health service’s most widely applied and totemic targets. The standard stipulates that at least 92% of patients should wait less than that time. But the NHS is currently failing to deliver this for the 4 million people on its waiting list. Last year QualityWatch reported on the growing problem of treatment waiting times and the situation has only worsened since.
One of the radical changes floated in the recent review of NHS access targets is to switch from a maximum wait to an average wait target for planned care, as proposed for A&E. This would mean the end of the 18 week target, or anything resembling it. What would the impact of this be on hospitals and on patients?
What would the average wait look like as a measure?
Measuring the mean or average wait would take into account how long all patients wait, rather than just monitoring a maximum wait, and that is arguably a good thing. As the review states, timely access to treatment is “what matters most clinically, and to patients”, and this applies throughout a patient’s pathway.
Waiting times can be measured in a number of ways, and each will provide us with different information. Currently, median waits and the 92nd percentile are routinely reported by NHS England each month. The figure below shows that the median wait has been increasing over time, and the steeper slope of the 92nd percentile indicates that people waiting the longest for treatment are being affected disproportionately.
Mean waits, which consider the total time that every patient has been waiting and give more weight to long-waiters, are not routinely published. But using data on the number of people waiting by week since referral, we can estimate that the mean wait in January this year was 9.6 weeks. This is a significant increase from a mean wait of 7.3 weeks in January 2013 (see Figure below).
It is not yet clear how a target based on average waits would be formulated, and how ambitious it would be. The aim could be to reduce the mean wait to a particular length of time, or to maintain current mean waits to prevent any further deterioration.
From a patient choice point of view, switching targets might not make that much difference. Mean waits and performance against the current target are strongly correlated at a hospital level, so there may not be any additional benefit in terms of informing patients on where to access treatment. There could be an increase in discontent, however, as a mean wait target would encourage patients to compare their wait with “the average”, and many patients would be waiting much longer.
From a hospital’s perspective, it may change the incentives of how to prioritise care which in turn would make a difference to patients.
Will perverse incentives be removed?
A clear problem with the current referral-to-treatment target is the cliff-edge drop in incentives for hospitals to treat patients who have been waiting longer than 18 weeks. Although there are financial penalties for trusts with patients waiting over one year, there is no formal incentive to promptly treat patients waiting between 18 and 52 weeks.
Depending on the sanctions associated with the new target, a standard based on the average waiting time is likely to incentivise trusts to treat the longest waiters first. This is because they carry the greatest mathematical weight. The current long tail of waits is apparent in the figure below, with a kink at 18 weeks that indicates an increase in the scheduling of patients the week before they reach the treatment target. However, as has become increasingly clear over the last few years, setting targets alone does not automatically improve performance – especially given budget and resource constraints.
How trusts react under a new mean-based target is an empirical question that the field testing the review proposes will need to monitor. Hospitals that are missing the target may try to reduce their average wait in different ways. A question for the trial of any new target is whether we are happy with the trade-offs that result.
What if it means longer waiters waiting less time, while shorter waiters wait longer? Or the other way around? We will need to think carefully about what trade-offs are acceptable both clinically and ethically, and what delivers the best outcomes and experience for patients.
The review of access standards suggests that the target could also penalise clinicians and hospitals for restructuring their outpatient services as set out in the NHS Long Term Plan. The Plan has an ambition to reduce face-to-face hospital-based outpatient visits by up to a third. But waiting times for the four fifths of planned patients who are waiting for an outpatient visit are significantly shorter than for a hospital admission. So hospitals which reduce the number of outpatient visits could make their average waiting time performance worse by removing some of the shorter waits – even though they are treating everyone who remains just as quickly as before.
This brings back to light the question of whether admitted and non-admitted patients should be grouped together on the elective waiting list and prioritised in the same way. There were previously separate targets for both groups, though these were removed on the recommendation of Sir Bruce Keogh in 2015. The issue is not being assessed in the current standards review, but perhaps it will be raised once again further down the line.
NHS England and NHS Improvement will field test the use of average waiting times in sites across the country. We will need to closely monitor patient outcomes and experience – and the way that priorities might shift. If history is any guide, field testing may even uncover new perverse incentives that have not yet occurred to NHS leaders or to us. It is time to watch and wait.
Morris J (2019) "The tipping point: considering the impact of the proposed changes to treatment waiting time targets" Nuffield Trust comment.