About the data

The cost of healthcare is rising and if the national health service is to survive as a tax funded service it must do everything it can to contain costs without reducing the quality of the service.

Central to this effort are new targets to reduce the number of emergency admissions to hospital. Emergency admissions to hospital are expensive and are often avoidable. The challenge for primary care trusts - which are responsible for buying both primary and secondary care for their populations - is to find ways of reaching the patient before they are rushed into A&E with severe problems and to ensure that if they do end up in hospital, they can be discharged as quickly as possible into the care of their GP and community services.

The table gives a range of measures for each PCT in the country relevant to this effort:

1) The deprivation index. More deprived areas tend to have higher levels of emergency admissions. We have divided PCTs into five equal groups. The most deprived fifth are rated 5, the least deprived 1. The figures are calculated using the Index of Multiple Deprivation 2004.

2) Standardised Admission Ratio (SAR) . This figure tells you whether the level of emergency admissions is higher or lower than expected given the age, sex and level of deprivation of the PCT's population. National average rates of emergency admission are calculated for each age, sex and deprivation group. The level of admissions in each PCT is then compared to the level you would expect for that population, given national averages. A figure of 100 means admissions are in line with the expected average rate. A figure of 110 means admission are 10% higher.

3) SAR band. This tells you whether we can say with 95% certainty that the level of admissions is higher or lower than average taking into account the margin for error. Figures in the average band may be higher or lower than 100 however the margin for error around the figure overlaps 100 meaning that we cannot be certain it is different from average. Those in the high or low band show statistically significant difference from the average.

4) Length of stay. This is the average number of days spent in an acute hospital bed following emergency admission for a stroke.

5) Waiting time. This is the average number of days waited for an inpatient treatment at hospital. Hospitals with longer waiting lists may experience higher levels of emergency admissions if patients deteriorate while waiting for care and then have to be treated as an emergency.