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Unearthing fundamental flaws about the central premises of both sides of a long and hotly contested argument is some feat. People usually opt for trying to skewer one side or the other.

But an intriguing new study on emergency department closures appears to have done just that.

The study published this week by Sheffield University academics scrutinised the closure of five hospital emergency departments between 2009 and 2011 and the impact on mortality rates.

It concluded the closures had not resulted in more deaths – a concern often cited by campaign groups seeking to block downgrades. But it also found the closures, and the always disruptive reorganisation required, had not improved patient outcomes either – an argument often cited by NHS policy makers pushing through such reconfigurations.

An important caveat to make up front is that neither the report authors nor anyone else are suggesting the findings can be extrapolated in their entirety to any local system across the NHS which is reconfiguring its emergency services.

The study (like any research of its kind) has limitations: it did not evaluate the impact closures had on neighbouring health economies, for example. And, some experts said a longer period of examination than the two years scrutinised in the study would have given the study more statistical rigour.

Another issue is the longest additional journey time resulting from the downgrades in this study was 25 minutes (with an average of nine). Other non-UK studies have found mortality was impacted by journey times. But they were looking at far longer additional journey times, closer to 50 minutes.

While England is relatively small, one respected policy expert argued that there were English NHS reconfiguration proposals where additional journey times could breach 30 minutes, and this could impact mortality rates. All are avenues for further investigation.

But the findings should certainly prompt system leaders to consider their ideological approach to A&E reconfiguration, which has to date been based on precious little in the way of robustly evidenced research carried out in the UK.

Nuffield Trust chief executive Nigel Edwards told me that as well as skewering the “save our A&E or people will die” argument, it also laid bare the insufficiently nuanced use of the evidence on both sides of the argument.

“This may give people pause for thought before blithely claiming there are going to be big economies of scope and scale in urgent and emergency care reconfiguration. Anecdotally, there is evidence of diseconomies of extra complexity,” he said.

Report author Emma Knowles hopes it could help address public misconceptions. She said: “When you ask some members of the public what they think will happen if their local ED closes, they are concerned that ‘people will die’.

“But what was reassuring for us was there was no change in mortality, either overall or individually within the five sites. This was a consistent finding across all the sites.”

Of course, workforce shortage is a crucial consideration when considering any reconfiguration. But few view the argument that a service should be shut down because of a failure to secure the appropriate workforce as a good one, and that is a different, albeit related, debate.

So, what is the answer? The problems in A&E departments are of course largely a symptom of wider system pressures, and cannot be addressed in isolation, which is why efforts to increase systemwide flow are rightly at the forefront of system leaders’ minds.

But if the NHS was redesigned from scratch today, there would certainly be nowhere the 185 type one A&Es there are at present. So further, painful reconfigurations are inevitable.

One option, some senior figures told me was quietly making a case, is the controversial hybrid model being trialled in places like Grantham, Lincolnshire, and Weston General Hospital in Somerset.

Bosses at both trusts took the unpopular decision to partially close the A&E at night but retaining a 24/7 urgent care centre service, pointing to staff shortages as the main driver.

Both trusts badged the measure as “temporary” until safe staffing levels were met. But it is two years this month since United Lincolnshire Hospitals Trust implemented the Grantham move and just over a year since Weston took the plunge.

Proponents say that the results so far in both places are building a case that it is a safe model. They argue that only a small proportion of ambulance admissions arrive overnight – and they can be quickly transported to other nearby A&Es at this time as there is far less traffic.

Further evaluation of the impact on patients in both hospitals’ local economies and the ripple effect on neighbouring hospitals would be well worth exploring.

It would be naive to think that one study will either dispel public anxiety about A&E closures or shift system leaders’ long entrenched views. But it should at least stimulate debate and be used as a platform to develop a broader evidence base to underpin decisions made about future reconfigurations.

The five A&Es involved in the study were: Newark, Rochdale, Hartlepool, Bishop Auckland and Hemel Hempstead. You can read the full study here.

UPDATED on 17 August: The piece was updated to reflect that the longest additional journey time resulting from the downgrades in this study was 25 minutes (with an average of nine). Other non-UK studies have found mortality was impacted by journey times, but they were studying longer additional journey times.