The new plans aim to cut hospital stays by tracking admission rates among older patients and then using specially trained nurses to care for them at home. But Martin Roland and colleagues show that this approach could be seriously misleading because admissions would probably decline anyway, without intervention.
To test their theory, they tracked emergency admissions in people aged 65 or more who had had at least two emergency visits to hospital in one year. This is the main criterion for admission to the Evercare programme* (which the authors are also evaluating) and one of the criteria being used to identify patients for enrolment in the NHS community matron scheme.
This 'high risk' group was monitored from 1997-8 to 2002-3 and compared with the general population of the same age.
They found a sharp decrease in total admissions and bed days over the five year period. The 65 to 74 age group had an admission rate 20 times greater than the general population of the same age in 1997-8, but this ratio fell to 5.2 in 1998-9 and by 2002-3 it was 1.7.
The entire group, comprising 2.9% of the total population of England aged over 65 in mid 1997, accounted for 38% of emergency admissions in 1997-8 but only 3.2% in 2002-3.
The authors say that further research to refine the definition of 'high risk' groups for interventions to reduce admissions is needed, and they warn that the effectiveness of admission avoidance schemes cannot be judged by tracking admission rates without careful comparison with a control group.
"When evaluating case management by community matrons, methods and outcome measures will need to be chosen with care to ensure that the true effect of this initiative on emergency admissions is measured," adds Professor Jill Morrison in an accompanying editorial.
She believes that the wider impact of the plan to transfer 3000 experienced district nurses or other health professionals from their current roles to undertake this new role should also be considered because this might leave gaps in the delivery of other community based services.