Fears have been raised that GPs are facing a major recruitment crisis, with figures showing a third of Scotland's family doctors are likely to retire in the next decade.

In addition, doctors are also having to cope with larger practices and increasing numbers of elderly patients.

Figures showed there are 4,938 family doctors working across the country but of those 1,680 - 34% of the workforce - are aged 50 or above.

List sizes have increased by 10% between 2005 and 2015, with practices now having an average of 5,736 patients to care for, compared to 5,206.

At the same time, the number of over-65s who are registered with a family doctor has risen from approximately 834,000 to 985,000, an 18% increase over the decade.

The figures were released as it was announced Scotland is to become the first part of the UK to scrap a bureaucratic system for funding GP practices.

Under the Quality Outcome Framework scheme (QOF), payments to surgeries were linked to how well they performed against a range of criteria.

It will come to an end from April next year, with practices receiving cash in core funding instead, with no reduction in payments for individual practices.

Health Secretary Shona Robison said the change was part of the Scottish Government's efforts to redesign primary-care services to make them "fit for the future".

But Labour and the Liberal Democrats raised concerns about the future of GP services.

Labour's Dr Richard Simpson, a former GP, said: "Under the SNP's watch, we are staring into the face of a major GP recruitment crisis."

Liberal Democrat health spokesman Jim Hume called on ministers to "get an urgent grip on primary-care services".

Ms Robison said: "We recognise that many GPs are facing particular challenges with recruitment and retention, as well as seeing more patients through their doors with more complicated needs.

"Indeed, statistics published today show that while the number of GPs working in Scotland has increased by 9% since 2005, the number of patients over 65 has also increased by 18% over the same time period."

Dr Simpson said the latest figures showed the "growing severity of the deterioration in general practice and vindicates Scottish Labour's concerns first raised and dismissed by the SNP in 2010".

He added it was "unacceptable" that figures for the number of full-time equivalent GPs have not been available since 2013, saying this "is the most important data for determining workload".

"We can infer from the numbers of patients per practice that there are far too few GPs and Scottish Labour's survey showed a shortfall of 500 GPs," he said.

"After eight years in government, a majority in parliament and more power than ever before the SNP have no excuses for their failure to act sooner to protect our health service."

Lib Dem MSP Mr Hume said: "When people are ill, their local GP is more often than not the first member of NHS staff that they come into contact with. They play a hugely important role in communities across Scotland.

"We know that the pressure on GPs is going up but real-terms funding has gone down, year on year, since 2009.

"It is no wonder that a Liberal Democrat survey found one-third of GPs would reconsider their career choice if they had their time again. A failure to invest in primary care has left doctors at breaking point."

Ms Robison said the removal of QOF points from the payment system would mean doctors spending less time on paperwork and more time with patients.

She said: "Today's announcement of the removal of all QOF points from the next GP contract marks a significant shift towards placing more trust in the clinical judgement and professionalism of GPs.

"While over the years QOF has delivered many innovations, its time has passed and we must now look to a new and different future for GPs.

"This important change to the payments system will mean GPs can spend less time on paperwork and get on with the job of treating patients who need them most."

Speaking later during a Scottish Parliament debate on redesigning primary care, Ms Robison said that from 2016 the number of GP training places would be increased by 33% and the Government is investing in a programme to encourage GPs who have left to return to the workforce.

She said: "We absolutely value family doctors, we want them to stay in the profession.

"We will have the first version of the new Scottish contract in place by April 2017, so by then we will have made significant progress to change the way GPs work.

"We will remove the the annual churn of contractual change and introduce the next version of the GP contract three years later in 2020."

She added: "As we move forward into next year, health and social care integration is presenting us with a huge opportunity to do things differently.

"My vision is of primary and community care very much at the heart of the healthcare system, with highly-skilled, multi-disciplinary teams delivering care both in-hours and out-of-hours, with a wide range of services tailored to the local area."

Dr Simpson said there should be "a fully-resourced shift in the balance of care from acute hospitals to a modernised, integrated, community health and social care service fit for the 21st century".

"There are clearly funding restraints and the next Parliament will need to consider how we address the reduction in the primary care budget," he said.

"Shifting the balance of care cannot be achieved without a significant shift in the balance of resource."

Mr Hume said: "The redesign of primary care for Scotland's communities must be precisely this - a redesign for communities.

"We are facing next year a project of enormous scale - the integration of health and social services will jointly manage £8 billion worth of assets and resources.

"The Scottish Government has to redesign services with regard to the real needs of the populations in different communities across Scotland.

"Unless that changes in a way that enables and empowers practitioners to plan for their patients, I think we will see very little progress in reducing inequalities."

Conservative MSP Jackson Carlaw warned that service redesign would dominate the next Scottish Parliament.

"This is the great strategic health debate and strategy decision that we have to make."