Aim: To compare, over a 4-year period, a cohort of adult frequent attenders at Christchurch Hospital Emergency Department (Christchurch, New Zealand) who received case management with a cohort who did not.
Method: A descriptive prospective cohort study of patients who attended ED 10 or more times during the index period of 1 Nov 2000-31 Oct 2001 was carried out. Each patient had an individual management plan. Attendance patterns were compared with a previous 4-year study of patients without management plans which was performed in the same ED. This study acted as an historical control.
Results: 87 patients who met the criteria for frequent attendance were compared with 77 patients in the control group. 10 patients remained frequent users for all 4 years of the study, compared with 9 in the control group. Most patients attended less frequently in the second year, with attendance rates continuing to fall, while a small group continued to make frequent presentations. The percentage of the cohort still attending ED at least once a year in the 4th year was nearly identical in each study (65% in the control and 64% in the intervention group); the percentage of each cohort who remained as frequent attenders, still attending 10 or more times in the 4th year, was identical.
Conclusions: This study showed similar rates of attrition in ED attendance between the cohorts with and without management plans. If there were not a 'control' group, the decline in attendance in the study group might have been attributed to the management plans. When attributing changes in attendance patterns to any intervention, it is important to be aware of natural attrition over time.