Low morale and poor pay are key reasons why the NHS struggles to retain staff, according to a new survey.

A poll of 2,000 NHS workers found that structural reorganisations of the NHS, such as those pushed through by the former Health Secretary Andrew Lansley in 2012, have also affected how staff feel about their work.

The King's Fund think tank has heavily criticised those reforms, saying they were "damaging and distracting". It also sees the creation of new sustainability and transformation plans (STPs) as a "workaround" of Mr Lansley's reforms.

The new poll, for Wilmington Healthcare UK, found 92% thought low morale caused problems with staff retention.

Some 72% also thought poor pay and rewards affected retention.

Looking ahead, most (85%) staff said access to training and development was a key requirement for the future NHS workforce, with flexible working and career progression also scoring highly (both 78%).

Almost half (48%) though Brexit would make it more difficult to recruit and retain staff but 45% said it would make no difference. Only 7% said it would be easier to recruit and retain staff.

Asked specifically about the GP workforce, which is beset by recruitment problems, half (52%) thought doctors should be paid more to work in unpopular locations.

Gareth Thomas, managing director of Wilmington Healthcare UK, said: "Our survey shows that continued changes in workforce planning since 2000 have been a major factor in NHS staff retention problems.

"This is of particular concern as the planned introduction of STPs is set to bring the biggest shake-up to NHS services since the publication of the Five Year Forward View.

"As the NHS moves towards a truly devolved health and social care system, it is clear that urgent action must be taken to support staff and help them manage the huge changes that are envisaged."

Unison's head of health Christina McAnea said: "Constant reorganisation of the NHS combined with years of low pay have seen staff morale plummet.

"Staff are leaving the NHS in droves, and the uncertainty over EU workers staying is only making matters worse.

"Ministers should stop taking health employees for granted and give them a decent wage rise."