Providing safe healthcare is "more complex" than setting a single ratio dictating how many patients should be assigned to each nurse, said the organisation behind NHS guidelines.
Professor Gillian Leng, deputy chief executive at NICE said:
Safe staffing is more complex than setting a single ratio. The emphasis should not just be on the available number of staff, it should be on delivering safe patient care and making sure that hospital management and nursing staff are absolutely clear on best practice to do this.
The reason why there is no single one-to-eight figure is because that will be seen as the figure that should be applied across all wards where we know that one to eight is not going to be enough in many scenarios.
A single figure is not appropriate if we want to deliver the right level of care for patients.
More top news
Labour leader will put support for public ownership at the centre of the party's campaign for May's local elections in England.
Scientists are researching a blood test which can quickly detect colon, lung, breast, stomach and endometrial cancer.
Transport bosses are said to be in "active discussions" with the company to encourage it to extend its pilot scheme to the UK's capital.