Inequality and its measurement

The existence of inequalities in health and death is rarely disputed, but there is contention over:

• Causes of inequality• Methods to monitor and measure• Extent of inequality, increase or decrease • What can be done

Inequalities indicators incorporate:• a measure (e.g. mortality rate, low birthweight

rate, unemployment rate)• an inequalities dimension (e.g. social class,

ethnicity, geographical area)• a comparison (e.g. rate ratio, range, relative or

absolute differences).– Eg births < 2500 gms / 1000 live births

• Change over time without reference to a comparitor population = health gain indicator only

• Compare between Las, PCTs, most and least deprived wards within a LA etc = health inequalities indicator

Health Gaps

A

C D

X axis: health measure eg teenage conception rates by LA

Y axis: frequency

Range = difference between best and worst (B-A)

B

National target measure (eg for life expectancy) = D – C

Ratio between highest and lowest = B/A (eg relative mortality rate between Social Class V and Social Class I)

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0 0.2 0.4 0.6 0.8 1

Cumulative % 15-17 year F population

Cu

mu

lati

ve %

un

der

18 c

on

cep

tio

ns

Line of equality PCT A PCT B

A

Measures of Spatial Inequalities in Health within PCTs

wards ranked from ward with lowest teenage pregnancy rate to ward with highest rate

On X axis: plot cumulative % population

On Y axis: plot cumulative % health measure

B

GINI Coefficient = A/(A+B)

= 0 perfect equality

= 1 perfect inequality

• Blue line PCT 9 wards

• Green line PCT 21 wards

• closer curved line (Lorenz curve) is to line of equality greater degree of equality

Measures of Spatial Inequalities in Health within PCTs

The trend in premature mortality rates is examined for each City deprivation quintile. A regression line is fit through the data for each quintile.

On X axis: plot time banded (3 year intervals)

On Y axis: plot DSR < 75 all causes per City deprivation quintile

Slope comparison across deprivation quintiles reveals progress in the most disadvantaged areas vs most affluent areas

Slope index of inequality

A regression line is drawn through a health measure stratified by a measure of socio-economic status

On X axis: plot average IMD2000 scores for ward deprivation quintiles in N&S

On Y axis: plot DSR < 75 all causes for ward deprivation quintiles in N&S

If slope reduces over time evidence of reduction in health inequalities