Figures shared with Nursing Times reveal the gulf in skill mix between different hospital trusts and regions.
Some standard acute trusts employ proportionately nearly twice as many clinical support staff - mainly healthcare assistants - in relation to registered nurses as other trusts.
The figures also show there is a three-fold difference between hospital trusts in the proportion of nursing and clinical support staff they employ who are senior nurses at band seven or above.
In many cases the variation is likely to be due to local differences such as the type of services, the way they are provided, or the jobs market.
However, Nursing Times was told that in some cases the figures reflect potentially dangerously low levels of registered nurses and support the case for compulsory regulation of healthcare assistants.
Regionally, the proportion of support staff varies by about 10 percentage points – although much of the difference may be accounted for by London as an outlier, with many specialist and teaching hospitals, and a competitive job market.
Of individual trusts, Taunton and Somerset NHS Foundation Trust has the lowest proportion of registered nurses (60.7%), followed by Mid Cheshire Hospitals NHS Foundation Trust (61.2%) and United Lincolnshire Hospitals NHS Trust, with 62.7%.
The Care Quality Commission is currently investigating Pilgrim Hospital, run by United Lincolnshire, in response to concerns about care. In the spring it said patients “do not always have their needs met by sufficient numbers of appropriately skilled staff”.
Three London trusts have the highest proportions of registered nurses: Newham University Hospital NHS Trust and West Middlesex University Hospital NHS Trust (both 78.4%) and Homerton University Hospital NHS Foundation Trust with 79.9%.
The figures have been released in the week the House of Lords debates a Health Bill amendments requiring healthcare assistants to be registered and minimum nursing numbers being stipulated in law.
Royal College of Nursing policy director Howard Catton said: “For large hospitals these variations mean a significant difference in the number of nurses.
“They appear to be greater than would be accounted for by purely clinical reasons, or because trusts are teaching or specialist hospitals.
“The reasons may be historic, or reflect regional trends or financial pressure.”
Mr Catton called on the government to investigate and impose appropriate nursing levels and skill mix for different service areas, considering both care quality and cost effectiveness.
He said enforced levels, combined with statutory regulation of healthcare assistants, could end the historic trend of “boom and bust in nursing levels”, with numbers swinging between safe and too few.
He said: “There is an opportunity to break that cycle with these amendments. They are seeking to guarantee safe staffing levels for patients.”
Sheffield University Hospitals Foundation Trust nurse director Hilary Chapman said statutory HCA regulation was unlikely but she supported the development of common education and training standards for HCAs among employers.
She said: “We could have an agreed standard across the country to which we prepare healthcare support workers. That would be a very positive step forward.”
Professor Chapman said the Nursing and Midwifery Council and Care Quality Commission should have a role in checking the voluntary system was being followed.
Southampton University chair of health services research Peter Griffiths said: “There will almost certainly be a very strong need to support some good practices [in nursing workforce] as a response to current calls [for regulation of HCAs].” He said employers this could include employers having to earn a “credential” for their HCA standards, although “it is unclear how it would be enforced”.
Taunton and Somerset Foundation Trust said in a statement its “matrons work clinically to ensure the nursing teams deliver high quality care to every patient and the support workers (band 3) at Musgrove [Park Hospital] receive additional training to enable them to work more closely with registered nurses in delivering safe and appropriate care to patients. This training includes taking observations and changing simple wound dressings, all of which is overseen by registered nurses”.
Its acting director of nursing Greg Dix said: “My priority is to ensure that all of our patients receive the very best quality care and experience. We are leading the way in implementing new initiatives - one of which is Intentional Rounding - which are further improving our already high standards of care. In addition to this Musgrove has recently been rated by the CQC as one of only four hospitals in the south west to be fully compliant against standards of care for elderly people. The results we consistently obtain from our patient surveys show that the care we are giving to our patients is of the highest quality.”
A spokesman for Mid Cheshire Hospitals said it “utilises the Association of UK University Hospitals acuity tool to monitor and assess nurse staffing levels based on acuity and dependency of patients”.
Chesterfield Royal Foundation Trust chief nurse Alfonzo Tramontano said in a statement: “The figures quoted for this trust may not be a like for like comparison. For example, our matrons are not part of this data - they are recorded as super numerary as they work in a supportive capacity - leading their wards.
“In addition, the roles of housekeeper, ward practitioner and healthcare assistants have seen development and expansion in the past few years - and the productive ward programme we are running has led to many changes. These staff groups take on some tasks previously undertaken by nurses - leaving nurses with ‘time to care’ and the ability to get ‘back to basics’.
“We are confident that our staffing structures provide quality of service and high-standards of care. This is certainly reflected in our national CQC assessments and in patient surveys.”
Figures provided to Nursing Times by the NHS Information Centre are for full time equivalents and include acute trusts only. They include all nursing staff, with midwives and health visitors excluded. Figures for clinical support staff exclude those supporting midwives and some administrative functions. However, a small number of management staff may be included for both.