Substituting nurses with nursing assistants linked to higher patient death risk, study warns

Reasearch shows one professional nurse substitution associated with a 21% rise in patient death risk.

Replacing professionally qualified nurses with lower skilled nursing assistants is linked to a heightened risk of patient death, as well as poor quality care, a ground-breaking study has shown.

For every 25 patients, just one professional nurse substitution was associated with a 21% rise in the odds of dying in a hospital with average nurse staffing levels and skill mix.


The study, which is published in BMJ Quality and Safety, prompted the RCN to warn the new role of nursing associate ‘cannot and must not be a substitute for registered nurses’ and authors of the report argue that diluting the hospital nurse skill mix is ‘not in the public interest’.

The research looked at survey responses from just over 13,000 nurses in 243 hospitals across England, Ireland, Belgium, Finland, Spain and Switzerland.

The study also analysed nearly 19,000 patients in 182 of these hospitals, along with discharge data for more than 275,500 patients who had undergone a surgical procedure in 188 of the hospitals.

The data includes information from the RN4CAST study, the largest nurse workforce study conducted in Europe.

Analysis showed a higher proportion of professionally qualified nurses were associated with:
  • A significantly lower risk of death.
  • Higher levels of patient satisfaction.
  • Fewer reported indicators of poor quality care, such as bedsores, falls, and urinary infections.


The average ratio of nursing staff to patients was 6 nurses to 25 patients, but ranged from 2.5 nurses to 14. The average percentage of professional nurses was 66%, but dropped as low in some cases as 41%.

The average hospital death rate was 12.8 for every 1,000 discharges and around 1 in 5 nurses rated the care on their unit as poor or fair.

Support staff risks

RCN chief executive Janet Davies said: ‘This research reinforces the stark fact – that for patient care to be safe and high quality, you need the right number of registered nurses. Substituting registered nurses with support staff quite simply puts patient care and patients’ lives at risk.’

Peter Griffiths, report author and chair of health services research at the University of Southampton said: ‘In Europe there has not been a study on this scale before, while it doesn’t directly reflect on any new roles of nursing associates as they don’t exist, it does add to the body of evidence showing there are significant risks with reducing skill mix of the nursing workforce.

‘I’d question why we are exploring nursing associates as a solution to a shortage of registered nurses as for many years we haven’t trained enough nurses we know are needed.’

A Department of Health spokesperson said: 'NHS staff are our greatest asset, and our plans will see 1,000 nursing associates complement, not replace, existing fully-qualified registered nurses and nursing care support workers.

'This will ensure that nurses can make the best use of their time in providing outstanding patient care.

'Specifically, these findings are based on research conducted between 2009-10 – which has no proper comparison with our new nursing associate role. Patient safety in the NHS has come a long way since then – we have implemented the Francis report following Mid Staffs, recruited over 10,000 more nurses to our wards, and patients say they have never felt safer in hospitals.'

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