THE new chief executive of beleaguered phone line NHS 24 has quit his post only six months after his appointment.

Ian Crichton, who was brought in to support the service after a major new IT system hit multiple delays and ran more than £40 million over budget, is taking a new job in the private sector.

Since he arrived at NHS 24, the service has twice launched the new technology for handling patient phone calls only to shut it down again amid fears slower response times were compromising patient safety.

With no firm date for a relaunch and the projected overspend running to £50m, NHS 24 has confirmed Mr Crichton is leaving at the end of this month.

Jackie Baillie, public health spokeswoman for Scottish Labour, said: "The timing of this departure clearly will cause concerns. It is absolutely imperative that the Scottish Government gets a grip on this.

"This IT project is tens of millions of pounds over budget and has been beset with problems and has had a number of different managers."

His decision to quit has emerged just three weeks after he was grilled at the public audit committee of the Scottish Parliament about the IT fiasco.

Spending watchdog Audit Scotland has already raised concerns that the personnel directly overseeing the project - known as the Future Programme - changed five times in five years.

Mr Crichton was appointed interim chief executive of NHS 24 at the end of August last year with a 15 per cent increase to his salary of around £134,000. He was moved from NHS National Services Scotland which supports health boards with administrative jobs such as procurement.

At the time the Scottish Government said the recruitment process for a new head of NHS 24 was underway and the role would be advertised in early September. No mention has been made of a replacement for Mr Crichton.

Under Mr Crichton the new technology was launched for the first time at the end of October but staff were told to use pens and paper after one hour amid concerns patient safety was at risk. In November the technology went live again, this time for 10 days. But the time it took to process patients almost doubled and the number of patients who hung up before their call was answered rose eight fold to 8000.

When Mr Crichton appeared before the Public Audit Committee, along with former NHS 24 chief executive John Turner - who quit last July, he told members: "From the very start, the organisation vastly underestimated the scale of the work and the complexity involved in bringing such an ambitious programme into service, and it has struggled to cope." But later he added: "We have genuinely committed people who, particularly in the past 12 to 18 months, have worked incredibly hard to get the programme into the state that it needs to be in, so that we can launch it. I expect us to do that in the coming year."

The latest board papers say the Future Programme is due to be rolled out again in June. They suggest workforce planning should assume productivity will halve during its first three months.

Ms Baillie said: "I hope that his [Mr Crichton's] departure is not an indication that the system remains flawed and beyond repair."

In a statement NHS 24 said: "Ian Crichton joined NHS 24 at the end of August 2015 on an interim basis. During his tenure Ian has lead the organisation through the busy winter period during which more than 75,000 calls were taken. Ian has shown exceptional leadership throughout, taking the difficult decision to delay the Future Programme roll-out in the interests of patient safety. We wish Ian all the best in his career. The NHS 24 Chair and Board are working closely with Scottish Government colleagues to put arrangements in place."

Ministers have drafted in well respected chief executives to troubled health boards before - but they have stayed in post. Malcolm Wright, who used to head up the training arm of the Scottish NHS, was sent to NHS Grampian on an interim basis and has now been appointed chief executive of that board. Tim Davison, chief executive of NHS Lothian, was initially drafted in following the waiting times scandal before being given the post on a permanent basis.

Scottish Liberal Democrat health spokesman Jim Hume said: "It is the Health Secretary's responsibility to ensure projects in her portfolio implemented by her administration are delivered on time and on budget with the right staffing in place to carry things forward.

"So, the news that NHS 24 is once again without a head when its new IT system has been delayed over and over again, while costs go up and up, calls for an urgent response from her.

"So far there has been a total lack of leadership on what has been a staggering failure in project management and she should be saying exactly what she plans to do to stop this spiralling any further out of control."

Scottish Labour also called on Shona Robison to respond.

Public services spokeswoman Jackie Baillie said: "The new IT system has been beset with problems for years, now NHS 24 is left without a chief executive and without a launch date for this system which is already massively behind schedule and tens of millions of pounds over budget.

"The SNP government need to get a grip on this and fast.

"At a time the SNP are making hundreds of millions of pounds of cuts across the country, this is an astonishing level of government waste."