It was Groundhog Day at Prime Minister’s Questions as Labour went on the attack again over the coalition’s handling of the NHS.

Ed Miliband painted a picture of dire mismanagement of the health service, with more people waiting for operations since David Cameron entered Number 10.

No, said Mr Cameron: fewer people are waiting for treatment than at any time under the previous government.

Shadow health secretary Andy Burnham raised a point of order, inviting the PM to correct the record, but Mr Cameron was unrepentant.

Who’s right?

The analysis

There’s a way in which both sides can be right about this, depending on how you shift the goalposts around.

Andy Burnham said the number of patients who waited more than 18 weeks for hospital treatment went up from 20,662 in April 2010 to 29,417 in April 2014 (the latest month we know about).

Labour’s health team later corrected the first figure when we contacted them, saying the actual number for April 2010 was 22,774. That’s still a rise of 29 per cent in four years.

The numbers stand up, but remember that the number of people seeking hospital treatment has also gone up over the last four years, so it’s not surprising that the number of late cases would rise too.

This is why the target for waiting times is expressed as a percentage of the caseload, not a raw number of people.

The target is for 90 per cent of people who are admitted to hospital to be treated within 18 weeks. The NHS narrowly hit this target in April 2014, after narrowly missing it in the previous two months.

The percentage of admitted patients being treated within 18 weeks is slightly lower now (90.0 per cent) than at the time of the election (92.1 per cent), but the difference is not dramatic.

So how can David Cameron say…

“The numbers waiting longer than 18, 26 and 52 weeks to start treatment is lower than at any time under the last government…?”

Because he’s talking about something different. Andy Burnham’s figures are for the number of people treated after the 18-week deadline. They’ve been treated late, but they have been treated.

David Cameron is referring to people who are still waiting for an operation. And yes, the numbers of people still waiting after 18, 26 and 52 weeks are lower than under the last government.

Here’s a graph from the independent King’s Fund watchdog on the percentage of patients still waiting after 18 weeks:

This comes as no great surprise to NHS-watchers, because the government only started enforcing targets on patients still waiting for non-urgent patients (“incomplete pathways”) after 18 weeks in 2012/13.

In the health service, when you highlight a problem and make managers work towards enforcement targets, you tend to see speedy improvements.

Nevertheless there has been real progress. When records began in 2007/08 there were more than 500,000 people still waiting for an operation after 52 weeks. Now the number is a little over 500.

The verdict

We’ve said it time and again: there are so many different NHS stats available that you can always cherry-pick something to show things are getting better or worse.

The government’s opponents can say, truthfully, that the percentage of people being treated within 18 weeks has been falling slightly since the 2010 election.

Average waiting times are also a bit higher now. But the picture is one of gradual decline rather than sudden crisis.

The government can say, equally truthfully, that the numbers of people waiting for long periods for operations has been cut, and that, as of April this year, the government is still (just about) hitting its 90 per cent target.

FactCheck’s strong recommendation is that, if you if you want a balanced overview of what’s going on in the health service, you ignore everything politicians say about the NHS at Prime Minister’s Questions and read the quarterly reports published by the King’s Fund.

The latest report sums up the current state of play thus: “The NHS in England has effectively had no real rise in spending between 2010/11 and 2013/14.

“Despite the challenge this has created, on key performance measures and based on our latest survey of finance directors, in broad terms the NHS has continued to provide services to a growing population and to maintain the quality of those services.

“However, there is deepening pessimism about the ability of the NHS to make ends meet financially, particularly in 2015/16.”