Transcript Socioeconomic inequalities in male mortality.

Socioeconomic inequalities in mortality: Men
aged 25-64 2001-3(4)
LS Clearance 20105D
Chris White
Principal Research Officer
Office for National Statistics
Introduction and context
• First official analysis of adult mortality by the final version of the National
Statistics Socio-Economic Classification (NS-SEC), updating previous
analysis by RGSC
• Sets benchmark for inequalities in premature death in early 21st Century
to enable future monitoring and compare impacts of different social and
occupational circumstances
• Intend to follow-up with further analyses covering:
– males and females of all ages
– patterns of inequalities in mortality by cause of death
– geographical area (GOR’s)
– independent influence of NS-SEC adjusting for other indicators of SES
Background
• Examinations of social inequalities in mortality generally
used one of two analytical approaches:
–Unlinked records approach
•advantages include detailed breakdowns, precise estimates
•disadvantages include numerator-denominator and health selection bias
–linked records follow-up approach
•advantages include numerator-denominator correspondence and possibility
to control selection
•disadvantages include small numbers constraining detailed breakdowns and
limiting precision
Objectives
• Assess the presence of biases through complementary linked
record analyses
• Adjust unlinked records estimates to optimise validity of
decennial results
• Measure remaining dissonance in estimates and examine
potential influences
• Compare analyses of all-cause mortality in men aged 25-64
by NS-SEC 9 analytic classes for 2001-3, using unlinked
records
• Assess conformity of the age standardised pattern by NS-
SEC across the age range
National Statistics Socioeconomic Classification (1)
• Delineates SE structure by employment relations not occupational
skill/perceived status
–Service relationship:
employee renders ‘service’ to employer in return for ‘compensation’
–Labour contract:
employee gives discrete amounts of labour in return for a wage calculated on amount of
work done or by time worked.
–Intermediate:
Forms of employment regulation that combine aspects of ‘service relationship’ and
‘labour contract’
• No manual / non-manual divide and greater within class homogeneity
and between class heterogeneity than was present in RGSC classes
• Distribution between classes is more even than with RGSC
National Statistics Socioeconomic Classification (2)
NS-SEC is derived from SOC 2000, employment status and
size of organisation
Analytic classes
1.1
Large employers and higher managers
1.2
Higher professionals
2
Lower managerial and professional
3
Intermediate
4
Small employers and own account workers
5
Lower supervisory technical occupations
6
Semi-routine occupations
7
Routine occupations
8
Never Worked and Long-term unemployed
Data Sources, study populations and data
issues
•
Death Occurrences 2001-03 and 2001 census, males aged 25-64 in
England and Wales
•
ONS Longitudinal Study sample enumerated in 2001, traced and
followed between census day and 31st December 2004
•
Coding of occupation at census
– Filter x
– Reduced NS-SEC
•
Health selection – assigned NS-SEC90 class from LS members 1991
census record if assigned to an unoccupied NS-SEC in 2001
•
Under-enumeration at census 2001 (MYPE 2001,2002, 2003)
Optimising cross-sectional denominator
Count in '000
Source: Census 2001, MYPE 2001-3, ONS LSt - crown copyright
10,000
Unadjusted - Filter X rule present
9,000
8,000
Adjusted - Filter X & Selection
7,000
6,000
5,000
4,000
3,000
2,000
1,000
0
1.1
1.2
2
3
4
5
NS-SEC Analytic Classes
6
7
Other
Assessing numerator conformity
• Imbalance in NS-SEC allocation at census and death
– Classes 1.1 and 2 had lower proportion assigned at census
– Class 3 and Never worked and Long-term Unemployed had higher proportion
– Other classes were within margin of sampling variation
• Examination of LS census and death records showed systematic
misallocation of operational category L6
– occupations categorised as Intermediate distinguished by employment status
– All deaths (n=18) assigned to L6 occupations at census were assigned to L7
occupations at death due to difference in reporting of employment status
– age-specific adjustment factors generated and extrapolated to death
occurrences for period 2001-03
– results in > in deaths allocated to class 2 ( 9 % ) and < in class 3 of ( 23 % )
Designation of deaths by source
Source: Death Occurrences 2001-03, ONS LS - Crown copyright
25
DO adjusted
LS adjusted
PER CENT
20
15
10
5
0
1
2
3
4
5
6
NS-SEC analytic class
7
8
9
Age-standardised death rates per 100,000 PYRs by NS-SEC:
men aged 25-64, England and Wales, death occurrences 2001-03
Sources: 2001 Census, MYPE 2001-3, Death occurrences 2001-3, ONS LS - crown copyright
600
Unadjusted
Adjusted
500
400
300
200
100
0
1.1
1.2
2
3
4
NS-SEC Analytic Classes
5
6
7
Age-standardised death rates per 100,000 PYRs by NS-SEC:
men aged 25-64, England and Wales, LS sample 2001-4
RATE
Source: ONS Longitudinal Study - crown copyright
1200
1000
800
600
400
200
0
1.1
1.2
2
3
4
5
NS-SEC Analytic Classes
6
7
NW and
LTU
Age-standardised death rates per 100,000 PYRs by occupied NS-SEC:
men aged 25-64, England and Wales, cross-sectional sources 2001-3
and LS sample 2001-4
RATE
cross-sectional
LS sample
600
500
400
300
200
100
0
1.1
1.2
2
3
4
5
6
NS-SEC Analytic Classes
Sources: 2001 Census, MYPE 2001-3, Death occurrences 2001-3, ONS LS - crown copyright
7
Age-specific rates per 100,000 by NS-SEC:
England and Wales 2001-03
RATE
1800
1.1
1.2
2
3
4
5
6
7
1600
1400
1200
1000
800
600
400
200
0
25-29
30-34
35-39
40-44
45-49
50-54
55-59
60-64
Sources: 2001 Census, MYPE 2001-3, Death occurrences 2001-3, ONS LS - crown copyright
Summary of Findings (1)
• A clear social gradient in mortality risk for men aged 25-64 is present in
contemporaneous linked and unlinked data sources (2.11 – 2.82)
–Good discrimination of mortality risk between employment relations domains
–Consistent pattern of decreasing mortality in each adjacent class from class 7 - 1.1
implying intensity of service relationship : labour contract continuum is relevant
–Mortality differences found within employment relations domains will be concealed
in descriptions of inequalities using the most condensed version of NS-SEC
• The protective influence of class 4 reported in analyses for the period 1991-93 was
not found in this analysis
• The Never worked and Long-term unemployed have clearly distinct life chances
compared with men in occupied NS-SEC classes
• The pattern of age-standardised mortality by NS-SEC predominantly consistent
across age range examined
Summary of Findings (2)
• Differences between sources
– Linked record method produces a higher rate in class 1.1 and lower rate in class
7 resulting in a shallower gradient, but class differences only statistically
significant in class 7
– May operate through differential exposure to long-term unemployed in NS-SEC
and its capture at census and death registration
– A lower national rate for England and Wales observed in LS sample compared
with aggregate data
– Unknown rate of unobserved embarkation and under-enumeration of younger
men in 2001 census may be drivers of differences
– Some allocations to class 3 at death suspect: adjustment for operational
category L6 advised in mortality analyses by NS-SEC
– Use of optimised populations recommended to adjust for known biases
Limitations of the research
• Restriction to men aged 25-64 will weaken mortality gradient:
– higher risk of death from accidental and violent causes found in low
socioeconomic status younger men
• Health-related social mobility not examined, but necessary:
– potential explanation for mortality gradient
• Independent influence of NS-SEC on mortality not examined:
– How does it stack up against alternative socioeconomic characteristics such
as tenure, area deprivation, educational attainment
Publication
• The article will be published in:
HEALTH STATISTICS QUARTERLY
NOVEMBER 2007 ISSUE
Social inequalities in adult male mortality by the National
Statistics Socio-Economic Classification: England and Wales
2001-2003