The Welsh government has been accused of “manipulation” and “electioneering” by rival parties over changes to how NHS waiting times statistics are published.

The Welsh government has started to publish provisional data a month sooner than “official data”, which has a seven-week lag.

Without the change, the Welsh Labour government could have gone into next year’s Senedd election unable to show whether it had hit its targets of bringing the overall waiting list down by 200,000 and reducing two-year waits to zero.

Both the Conservatives and Plaid Cymru said this was a tactic to ensure the party looked good ahead of the poll in May, but the Welsh government rejected those claims.

New figures released on Thursday showed total numbers waiting for treatment on the NHS in July fell to just under 793,100, but the numbers waiting longer than two years rose to just over 8,000, an increase of 7.5% on the previous month.

In April, Health Secretary Jeremy Miles set his targets for the end of March 2026, but it would not have been possible to officially report on whether those targets had been met under the old health system before the Senedd election.

This is because the Senedd election is set for 7 May, just over five weeks after the end of March, with full data not confirmed for seven weeks.

If the provisional stats suggest the waiting list targets have been met it would be a powerful message to present to voters.

But there is also an inherent risk the figures could show the targets have been missed, creating political risk for the Welsh Labour government.

James Evans, the Welsh Conservative health spokesman, said: “I think the government should be producing the actual stats and not provisional stats ahead of time, which ahead of a Senedd election could end up making the government look good, which unfortunately is a bit of electioneering.”

Mabon ap Gwynfor, health spokesman for Plaid Cymru, said: “This a clear attempt to manipulate the figures by Labour in the hope that they will look better immediately before an election.”

“This change will do nothing to improve outcomes and will not cut the painfully long waiting lists that the people of Wales are having to suffer.”

In a statement the Welsh government said: “There is considerable public interest in NHS waiting times.

“Official statistics on this topic have a lag of around seven weeks, however NHS management information can provide a timelier indication of performance.

“Publishing this provisional data enables us to transparently communicate progress against Welsh government commitments and enable scrutiny of the NHS and Welsh government’s performance.”

BBC Wales has been told that decisions on statistics are taken independently by the Welsh government’s chief statistician, but that the health secretary had previously asked statisticians to explore whether more timely NHS data could be released transparently.

The change to statistics publication has been welcomed by the UK’s official watchdog, the Office for Statistics Regulation.

In the new figures released, those waiting longer than one year for an outpatient appointment in Wales increased to just under 73,200.

Provisional data published last month suggested both the overall numbers and two-year waits would rise, but the official data showed a slightly different result.

This month’s provisional data has predicted two-year waits will again rise, but the total numbers waiting will fall.

Elsewhere, while there was a slight drop in the average daily numbers attending A&E, performance against the four and 12-hour targets worsened.

Changes to the way ambulance performance is measured suggests an improvement in the rate of those arriving at hospital with a heartbeat following a cardiac arrest.

Cancer waiting times showed a slight improvement at 61% starting treatment within the 62-day target.

Evans, the Welsh Conservative health spokesman, called the figures “yet another abysmal failure” for the Welsh Labour government.

“Labour is throwing more and more money at this problem, but isn’t seeing results. We need to see red tape, the ballooning bureaucracy and wasteful spending cut. We don’t need more middle managers – focus on the frontline,” he said.

The length of NHS waiting lists in Wales is likely to be one of the key battlegrounds at next year’s election.

Labour’s record after 26 years in power as well as proposals put forward by the other parties including Reform and the Liberal Democrats will come under intense scrutiny.

But while the politicians argue, waiting times have real consequences for people like Stephen Pitcher.

The retired geography teacher, from Ystalyfera, Neath Port Talbot, was expecting to celebrate his 70th birthday in the company of family and friends.

But instead he spent it alone in a hotel room in Lithuania recovering from hip replacement surgery after being told he could expect a three-year wait for NHS treatment.

A keen traveller, it was on a family holiday in Canada this summer when things suddenly took a turn for the worse.

He said: “I was… having a great time, white-water rafting, hiking, canoeing, kayaking, and in the last week, in early July, my hip just went off a cliff.

“Within a matter of days, I went from being able to hike quite happily to limping and being in pain.”

On his return home, Mr Pitcher was told by his GP he would have to wait for a minimum of three years for surgery, as he would also have to go through physio before joining a waiting list.

Unable to bear the prospect of spending so long in pain, he used money inherited after his father’s death the year before to pay £7,500 for the procedure in Lithuania, which was arranged within weeks.

He said: “The price [of the surgery] was less than a second-hand car.

“Nonetheless, I thought it was going to be money well spent.

“The idea of sitting here in pain for two, three years… it wasn’t a long and arduous decision to make. It was made in a split second.

“I won’t get a new car, I’ll keep the old one, and go and get this done. And I’m so pleased that I did.”

Six weeks on from the operation, he said he was hoping to be back walking in the rugged countryside near his home soon, but he realised many others would not be able to afford to do what he did.

He said: “I wouldn’t ever knock the NHS. I mean, everyone who I’ve met who works in the NHS are wonderful, and they do all they can. But I would knock the politicians and those who fund the NHS.”