8.1 Introduction

The last Census in 2001 offers a useful comparison of deprivation levels across the decades. There appears to be a widening gap in deprivation indices across the decades (McCarron 1994, McLoone1994, Phillimore 1994) The problem with addressing this issue, is that many articles use deprivation indices that were relevant to 1991 and 1981 census. The most often used deprivation indices are Townsend 4 and Jarman 8 scores. However the Office of National Statistics (ONS) and the Office of the Deputy Prime Minister have utilised a more wide ranging basket of indices which are known as the Index of Multiple Deprivation of which the current version is 2004 (IMD 2004).

There has been considerable interest in comparing different forms of Deprivation Score. However a search on Pub Med, BMJ and Medline indicate that no papers have been published since the last census comparing these different indices (search criteria comparison deprivation score). The databases searched include the following

Allied & Complementary Medicine - 1985 to date (AMED)
British Nursing Index - 1994 to date (BNID)
CINAHL (R) - 1982 to date (NAHL)
DH-DATA - 1983 to date (DHSS)
EMBASE - 1974 to date (EMZZ)
EMBASE - 1996 to date (EMED)
King's Fund - 1979 to date (KFND)
MEDLINE - 1950 to date (MEZZ)
MEDLINE - 1996 to date (MEDL)
PsycINFO - 1806 to date (PSYC)

8.2 Background

The Townsend Material Deprivation Index is made up of the following 4 Census 1991 variables:

• Unemployment – unemployed residents over 16 years as a % of all economically active residents aged over 16.
• Overcrowding – households with 1 and over persons per room as a % of all households.
• Non car ownership – households with no car as a % all households.
• Non home ownership – households not owning their own home as a % of all households.

It is important to note that the weight given to each of the 4 variables is equal – ie they account for 25% of the score. This is in sharp contrast to the Index of Multiple Deprivation and related domains which have unequal weights.

IMD 2004 is a composite index. It contains seven domains that relate to Income deprivation, Employment deprivation, Health deprivation and disability, Education, skills and training deprivation, Barriers to Housing and Services, Living environment deprivation and Crime.

The IMD 2004 index is a weighted index – ie the relative influence of each of these domains is not equal. The weights are as described below:

Table 8.01: Domains and Weights used in the Calculation of IMD 2004

8.3 Domains used in the calculation of IMD 2004

The domains are a composite of census and other variables derived from other government department statistics. These are updated at different time intervals and hence overcome one of the criticisms of the Townsend 4 scores as being a historical snap shot of the population on Census night.

The domains are described below and their composite variables are described accordingly:

8.3.1 Income Deprivation Domain

The purpose of this Domain is to capture the proportion of the population experiencing income deprivation in an area.

• Adults and children in Income Support households (2001).
• Adults and children in Income Based Job Seekers Allowance households (2001).
• Adults and children in Working Families Tax Credit households whose equivalised income (excluding housing benefits) is below 60% of median before housing costs (2001).
• Adults and children in Disabled Person's Tax Credit households whose equivalised income (excluding housing benefits) is below 60% of median before housing costs (2001).
• National Asylum Support Service supported asylum seekers in England in receipt of subsistence only and accommodation support (2002).

In addition, an Income Deprivation Affecting Children Index and an Income Deprivation Affecting Older People Index were created.

8.3.2 Employment Deprivation Domain

This domain measures employment deprivation conceptualised as involuntary exclusion of the working age population from the world of work.

• Unemployment claimant count (JUVOS) of women aged 18-59 and men aged 18-64 averaged over 4 quarters (2001).
• Incapacity Benefit claimants women aged 18-59 and men aged 18-64 (2001).
• Severe Disablement Allowance claimants women aged 18-59 and men aged 18-64 (2001).
• Participants in New Deal for the 18-24s who are not included in the claimant count (2001).
• Participants in New Deal for 25+ who are not included in the claimant count (2001).
• Participants in New Deal for Lone Parents aged 18 and over (2001).

8.3.3 Health Deprivation and Disability Domain

This domain identifies areas with relatively high rates of people who die prematurely or whose quality of life is impaired by poor health or who are disabled, across the whole population.

• Years of Potential Life Lost (1997-2001).
• Comparative Illness and Disability Ratio (2001).
• Measures of emergency admissions to hospital (1999-2002).
• Adults under 60 suffering from mood or anxiety disorders (1997-2002).

8.3.4 Education, Skills and Training Deprivation Domain

This Domain captures the extent of deprivation in terms of education, skills and training in a local area. The indicators fall into two sub domains: one relating to education deprivation for children/young people in the area and one relating to lack of skills and qualifications among the working age adult population.

The sub domain Children/young people comprises of the following;

• Average points score of children at Key Stage 2 (2002).
• Average points score of children at Key Stage 3 (2002).
• Average points score of children at Key Stage 4 (2002).
• Proportion of young people not staying on in school or school level education above 16 (2001).
• Proportion of those aged under 21 not entering Higher Education (1999-2002).
• Secondary school absence rate (2001-2002).

The sub domain Skills comprises of the following:

• Proportions of working age adults (aged 25-54) in the area with no or low qualifications (2001).

8.3.5 Barriers to Housing and Services Domain

This domain is to measure barriers to housing and key local services. The indicators fall into two sub-domains: 'geographical barriers' and 'wider barriers' which also includes issues relating to access to housing, such as affordability.

The sub domain  wider barriers comprises of the following;

• Household overcrowding (2001).
• LA level percentage of households for whom a decision on their application for assistance under
• the homeless provisions of housing legislation has been made, assigned to SOAs (2002).
• Difficulty of Access to owner-occupation (2002).

The sub domain geographical barriers comprises the following;

• Road distance to GP premises (2003).
• Road distance to a supermarket or convenience store (2002).
• Road distance to a primary school (2001-2002).
• Road distance to a Post Office (2003).

8.3.6 The Living Environment Deprivation Domain

This domain focuses on deprivation with respect to the characteristics of the living environment. It comprises two sub-domains: the 'indoors' living environment which measures the quality of housing and the 'outdoors' living environment which contains two measures about air quality and road traffic accidents.

The sub-domain  'indoors' living environment comprises of the following

• Social and private housing in poor condition (2001).
• Houses without central heating (2001).

The sub-domain  'outdoors' living environment comprises the following;

• Air quality (2001).
• Road traffic accidents involving injury to pedestrians and cyclists (2000-2002).

8.3.7 Crime Domain

This domain measures the incidence of recorded crime for four major crime themes, representing the occurrence of personal and material victimisation at a small area level.

• Burglary (4 recorded crime offence types, April 2002-March 2003).
• Theft (5 recorded crime offence types, April 2002-March 2003, constrained to CDRP level).
• Criminal damage (10 recorded crime offence types, April 2002-March 2003).
• Violence (14 recorded crime offence types, April 2002-March 2003).

The methodological steps that were taken to create the IMD 2004 are described in the full report found on the Office of Deputy Prime Ministers (ODPM) www.odpm.gov.uk

8.4 Aims of this Chapter

The purpose of this chapter is to provide a comparison between Townsend 4 scores and the Index of Multiple Deprivation 2004 (IMD 2004) and its constituent domains.  It has not been possible to compare the scores with health statistics, However this chapter will provide a correlation comparison between the scores to enable the reader to have a considered opinion as to which deprivation or domain score to use when.

8.5 Methodology

IMD 2004 data relating to super output areas was downloaded from the ODPM website. The data contained the IMD 2004 scores, constituent domain scores and ranks. The Townsend 4 scores were calculated at SOA level by the Department of Public Health and Epidemiology and the Department of Biostatistics at Leeds University.  Details of the methodology can be obtained if required. The following 8 graphs compare Townsend 4 (T4) scores with the IMD 2004 composite score and the domains.

8.6 Results

8.6.1 IMD and T4

Figure 8.01: Comparison between IMD and T4

Figure 8.01: Comparison between IMD and T4

There appears to be a close correlation between the two variables. The exponential equation appears to fit the data better, despite both scores being transformed.

8.6.2 Income Domain & T4

Figure 8.02: T4 and Income

Figure 8.02: T4 and Income

This describes the same correlation, but the R2 is better than with the IMD 2004.

8.6.3 Employment Domain and T4

Figure 8.03: T4 and Employment

Figure 8.03: T4 & Employment

There also appears to be an exponential relationship between the variables, but the regression coefficient R2 is not as large as the income domain or IMD 2004.

8.6.4 Disability Domain and T4

Figure 8.04: T4 and Health Deprivation/Disability

Figure 8.04 T4 and Health Deprivation/Disability

There is a linear relationship between the two variables and MS Excel was unable to draw an exponential trend line because both scores became negative.

8.6.5 Education Domain and T4

Figure 8:05: T4 and Education

Figure 8.05: T4 and Education

The relationship between Education Domain and T4  (figure 8.4) is not as correlated as the above, however there appears to be more of an exponential relationship between the variables.

8.6.6 Housing Domain and T4

Figure 8.06: T4 and Housing

Figure 8.06: T4 and Housing

There appears to be no correlation between these two variables

8.6.7 Environment Domain and T4

Figure 8.07: T4 and Environment

Figure 8.07: T4 and Environment

There is a relationship between these variables, but it is weaker than most of the previous domains.

8.6.8 Crime Domain and T4

Figure 8.08: T4 and Crime

Figure 8.08 T4 and Crime

There is a relationship between these variables, but it is weaker than most of the previous domains.

8.7 Discussion

This chapter describes the association between T4, IMD 2004 and it’s constituent domains. Policy and policy makers have used various indices when comparing, contrasting and informing the debate that surrounds policy development. In addition, health and health service researches have used this data to shed a light on various aspects of health service provision.

The production of the IMD scores not only allows a new model by which deprivation can be analysed but also provides a means by which historical trends can be made. However, for this to be done, a meaningful understanding between the different deprivation indices needs to be had. This chapter starts this comparison and it is for other researches to further the body of evidence relating to when, where and how these new census deprivation indices and domains are best used.

The strong associations between income domain, IMD 2004 and T4 scores resonates with views on the census variables. In particular, the importance of particular variables, particularly car ownership has previously been explored (Christie et al 2003, Ebrahim-shah et al 2004) as probably the most important census variable associated with health. The indicator which shows the best correlation between T4 and IMD 2004 is the income domain (Figure 8.02).

References

Christie-S-M-L, Fone-D-L. “Does car ownership reflect socio-economic disadvantage in rural areas? : a cross-sectional geographical study in Wales, UK.”  Public Health, March 2003, vol. 117, no. 2, p. 112-116.

Ebrahim-Shah, Papacosta-Olia, Wannamethee-Goya, Adamson-Joy. Social inequalities and disability in older men; prospective findings from the British regional heart study. Social Science and Medicine, Nov 2004, vol. 59, no. 10, p. 2109-2120.

Gilthorpe-M-S, Wilson-R-C. Rural/urban differences in the association between deprivation and healthcare utilisation. Soc-Sci-Med 2003 Dec; 57(11):2055-63,

Peter G McCarron, George Davey Smith, and John J Womersley Deprivation and mortality in Glasgow: changes from 1980 to 1992 BMJ, Dec 1994; 309: 1481 – 1482

Philip McLoone and F A Boddy Deprivation and mortality in Scotland, 1981 and 1991 BMJ, Dec 1994; 309: 1465 – 1470
http://www.odpm.gov.uk/index.asp?id=1128440

http://www.odpm.gov.uk/index.asp?id=1128440

Peter Phillimore, Alastair Beattie, and Peter Townsend Widening inequality of health in northern England, 1981-91 BMJ, Apr 1994; 308: 1125 - 1128