The investigators hypothesised:
1-Higher numbers of nurses on the ICU establishment will be associated with lower rates of patient mortality.
2-Higher numbers of consultants in an ICU will be associated with lower mortality rates.
3- Higher numbers of support staff in an ICU will be associated with lower mortality rates.
4-The higher the workload of the unit, the less likely individual patients are to survive.
This is an observational study where statistical controls are used to assess the relationship between the key independent variables of interest and the dependent variable.
It was found that the risk of mortality is significantly increased by the severity of the patient’s own condition, and by staff measures of workload.
The risk of mortality increases when a higher proportion of beds in the unit are occupied and when there are a large number of transfers into the unit. The number of nurses and the number of consultants both significantly reduce the risk of mortality. The hypothesis that the number of support staff would affect patient mortality is not supported.
The reduction in mortality risk from having more nurses is larger for patients who are the most severely ill.
What do you think?