Nursing workload in hospitals: Does it have an impact on the health of patients?

In German hospitals the number of patients each nurse needs to care for has noticeably increased. It is not yet possible to conclude whether or not this has had an effect on the quality of patient care in Germany.

The reputation of a hospital is often determined by its nursing care. It has been suggested that the burden of work on nurses, depending on their qualifications and task or specialty, might have an impact on the quality of a hospital's patient care. Or, to put it another way: if a hospital has too few nurses, this could theoretically have health consequences for the patients. This is why one of the basic questions for planning hospital staffing is whether or not there is a minimum number of nurses needed per patient to avoid patients being disadvantaged.

This question is important in Germany too. There are around 2,150 hospitals in Germany, and in recent years they have been reducing the number of nurses. Between 1995 and 2004 the number of people working in nursing full-time fell from over 350,000 to 309,000. Meanwhile the number of patients admitted to hospital rose. Altogether, the number of patients being cared for on average per nurse rose by almost 20% between 1995 and 2004. It is not possible to draw conclusions about the actual workload, though, because the tasks of a nurse can vary a lot depending on where they work. The staffing levels are different between intensive care units or a ward in a psychiatric hospital, for example.

With these considerations in mind, researchers from the German Institute for Quality and Efficiency in Health Care (IQWiG) gathered evidence on this question to see if nursing workload has been shown to have an impact on the quality of care in hospitals. They did not look at community nursing or aged care. The result: there is no established point to show when nurses are so overloaded that the quality of care begins to suffer. The researchers found 17 studies altogether that looked at this question. All of the studies were done in the USA, which means that there had not been reliable research in Germany on this question.

The US studies also had contradictory results. One of the problems is that there are many different ways that nursing workload can be measured. In many studies ratios such as "nurses per patient" were calculated, while others chose "nurses per occupied hospital bed". This means that it is not really possible to compare the results of different studies directly with each other. That makes it impossible to explain the reasons for the differing conclusions between studies with any certainty.

Some of the studies in US hospitals, for example, showed an association (or link) between the workload of nurses and the mortality rate of patients: the hospitals where each nurse had to look after higher average numbers of patients had higher mortality rates, too. However other studies that included larger numbers of hospitals did not show this result.

There were similar contradictions in the findings of studies where complications typical for hospital patients were studied. There was no association between nursing workload and various infections, pneumonia (lung infection) or bed sores. This could be because hospitals with extremely heavy workloads for nurses did not participate in the US studies.

In any event the results from these US hospitals would not necessarily have applied to the situation in Germany. There could be too many differences between the roles of nurses and their working situations.

The IQWiG researchers came to the conclusion that some studies in the USA suggest that when nurse workloads are too high, it can have consequences for the health of a hospital's patients. However research cannot pinpoint a specific nursing workload where this would begin. The most important finding of this research is that there is a need to study the relationship between nursing workload and the quality of hospital care in Germany.

© IQWiG (Institute for Quality and Efficiency in Health Care)