Interpreting the Life Expectancy at Birth Targets
The national Public Service Agreement (PSA) for improving the health of the population aims:
1. To increase the life expectancy at birth in England to 78.6 years for men and to 82.5 years for women by 2010 and;
2. Reduce the inequalities in life expectancy at birth by 10% between the lowest fifth of local authority districts (LAD) for ‘health and deprivation indicators’ and the average for England by 2010.
The national targets can be interpreted in a number of ways:
1. Absolute improvements in life expectancy at birth:
In theory to achieve the national target each LAD should aim for improvements in life expectancy at birth of 4.13 years for men and 2.95 years for women from years 1995-97 to 2009-2011. In addition, for LADs in the worst fifth a further improvement will be necessary to achieve a reduction in the relative gap by 10%.
Although this method will be useful for identifying where improvement is not being met at the pace demanded by the national target it is unrealistic in policy terms to expect LAD’s to improve at the same pace because:
- The life expectancy at birth target is influenced by many factors including changes in the population structure. For example, large improvements in life expectancy at birth are the result of changes in the characteristics of an areas population, e.g. migration in of higher social classes and migration out of lower social classes.
- To measure improvement from a baseline in 1995-97 when we are in year 2004/5 and expect an improvement is inequitable and will favour LAD’s which have gone through changes mentioned in point 1. For example, in 1995-97, Hammersmith and Fulham had a life expectancy at birth for men of 72.0 years the 13th worst in England whereas in 2001-03 the life expectancy for men was 75.8 years the 106th worst in England. The improvement in Hammersmith and Fulham is consistent for men and women.
- Short-term interventions to improve the life expectancy at birth will not produce the necessary absolute improvements for some LAD’s that have not improved or are getting worse.
2. Applying a stretch based upon current improvements
To avoid the problems of using an absolute improvement for all LAD’s progress can be monitored using a stretch to each LAD in the lowest fifth. The stretch is calculated by using projections to determine the neutral position in 2010 for the LADs in the lowest fifth for life expectancy. The neutral position for the lowest fifth is then compared with the national PSA target 1 (above) to determine remaining improvement needed in the lowest fifth as a whole to reduce the gap by 10%.
For example, if the gap in life expectancy at birth for men in 1995-97 between the lowest quintile and the England average was 2.5 years the gap should be reduced to at least 2.25 years (0.25 year reduction) by 2009-2011. If the neutral position for the worst fifth shows that the gap in life expectancy at birth has not decreased the stretch needed for each LAD in the worst fifth would include a 0.25 year increase on top of the neutral position.
This method provides a number of benefits from the absolute approach:
- It considers the current progress in life expectancy at birth (since 1995-97), which is affected by the wider determinants of health (discussed above), which are independent and interrelated to improvements that can be made by NHS interventions alone.
- This method provides a realistic life expectancy at birth improvement for LAD’s in the lowest fifth for health and deprivation. This in turn will help identify the key interventions, which can be used to bridge the small gap between the neutral position and the short-term national improvements needed by 2010.
NB. This process must to recognise the wide variations in life expectancy at birth at the LAD level and the disproportionate changes that have been made since 1995-97. This will highlight the affect that the wider determinants of health have upon an areas life expectancy at birth (e.g. migration).
The target will be monitored using Local Authority Districts (LAD) because of the relative stability of their boundaries and the availability of historic populations.
This group of LAD’s is fixed from the baseline years (1995-97) to the target years (2009-11)
and is based upon 5 health and deprivation indicators.