Patient dependency in the emergency department (ED): reliability and validity of the Jones Dependency Tool (JDT)

Rising patient demand in emergency departments is an international problem. Patient dependency (the degree of nursing care required) has major implications for nursing. Nurse skill mix and staffing levels can be addressed more effectively when dependency can be measured. A valid and reliable method of determining patient dependency in the emergency department in the United Kingdom is required.

To test the validity, reliability and generalisability of the Jones Dependency Tool.

Six emergency departments across England were included. The sample was 140 adult patients from each site (n=840). Information was collected by nurses on: demographics, triage, chief complaint, vital clinical signs, nurse's own subjective rating of patient dependency, Jones Dependency Tool ratings and a comparative tool ratings. For a sub-sample of 40 patients, observation data were collected.

There was a highly significant correlation between the Jones Dependency Tool scores and the nurses' subjective ratings of patient dependency (R=0.786,P<0.001). There was a significant correlation between triage rating and Jones Dependency Tool scores (R=0.58,P<0.001). The higher the dependency, the higher the proportion of patients with abnormal pulse rates (chi2=7.45,df=1,P=0.006), abnormal respiratory rates (chi2=15.683,df=1,P<0.001) and abnormal oxygen saturation (chi2=15.583,df=1,P<0.001). The higher the amount of time spent by nurses in direct care of patients the higher the patient's level of dependency (R=0,72,P<0.001). Length of time spent by nurses with patients was also significantly and positively correlated with the nurses' subjective ratings of patient dependency (R=0.49,P=0.001). There was a positive and significant correlation between Jones Dependency Tool scores and comparator scores (R=0.726,P<0.001). There was a good correlation between JDT scores measured over time (kappa=0.68) and good inter-rater reliability (kappa=0.75).

The Jones Dependency Tool can be recommended as a valid and reliable tool for the measurement of patient dependency in the emergency department.