Transcript Slide 1

Aims of Presentation
• “Uses of Health Examination Survey
in England” – Health Survey for
England (HSfE)
• Why England incorporated an
examination component in HSfE
• Personal
• Medical epidemiologist
• Public health doctor
• Organisational
• Department of Health (England)
• Health monitoring unit
• Policy directorate (public health)
Current review of Survey
The Health Survey for England has been
commissioned by the Information Centre for
health and social care (IC) since April 2005;
and carried out since 1994 by the Joint Health
Surveys Unit.
• The IC is currently undertaking a review of
the entire survey programme.
Early history - context
• Late 1980s
• Chief Medical Officer
• Health strategy
• Identify key issues
• Targets
• Health survey
• Fact finding in USA
Why a health survey? [1]
• Information needed for all stages of policy
making process:
Strategy development
Policy initiation
Option appraisal
Why a health survey? [2]
Good information on various aspects:
• Mortality data
• Cancer incidence and survival
• Information on use of services:
– secondary care (good)
– primary care (limited)
• Self-reported behaviour (risk factors)
Why a health survey? [3]
• Other surveys
– Specific eg diet and nutrition
– Health questions in general household
• Research studies – eg Whitehall studies of
civil servants; British Regional Heart Study
• But insufficient for supporting a health
Why a health
examination survey?
Only limited information on objective
measures of health and risk factors
Distribution in the population
socio-economic measures
• Finance
• Opportunity costs
Political factors
• Priorities
• Identifying undetected or untreated disease
Initial focus
Issues (2)
Sample size
Geographical coverage
Topic coverage
One stage or two stage
Trained interviewers vs Nurses
Effects on response rates
The Health Survey for
England (HSfE) – early years
• Annual survey about the health of people in England.
• First proposed in 1990 to improve information of
morbidity and determinants of health.
• Information for use in underpinning and improved
targeting of nationwide health policies.
• The survey was carried out in 1991-1993 by the Office
for Population Censuses and Surveys which is now
part of the Office for National Statistics.
• From 1994 onwards the survey has been carried out by
the Joint Survey Unit of the National Centre of Social
Research and the Department of Epidemiology and
Public Health at University College London.
HSfE – initial aims
• to provide annual data about the nation's health;
• to estimate the proportion of the population with specific
health conditions;
• to estimate the prevalence of risk factors associated
with those conditions;
• to assess the frequency with which combinations of risk
factors occur;
• to examine differences between population subgroups;
• to monitor targets in the health strategy;
• (from 1995) to measure the height of children at different ages,
replacing the national study of health and growth.
The Health Survey for
England (HSfE) – 1991-93
• Cardiovascular focus
• Initial limited sample size
• Adults
• Addressed key priorities – supported Health of
the Nation strategy (including 2 targets)
'Core' topics
general health
smoking and drinking behaviour
blood pressure
height and weight
other anthropometric measures
prescribed medication
fruit and vegetable consumption (since
Why continue the HSfE
Ongoing need for monitoring trends
New policy priorities (see next slide)
Frequency of assessment
Stop/start process logistically unhelpful
Added value of new data
– Monitoring
– Amalgamating years for more local data
The agenda evolves
Non-Core' topics (1)
• cardiovascular disease (1991-94, 1998, 2003)
• asthma + other respiratory diseases (1995-97)
• lung function (1995-97)
• atopic conditions (1995-96)
• eating habits (1993-94, 1997)
• physical activity (1991-94, 1997)
• accidents (1995-97)
The agenda evolves
Non-Core' topics (2)
• General Health Questionnaire (1991-95, 1997)
• generic health state measures EuroQol and SF-36 (1996)
• disability (1995)
• contraceptive use (1992-95, 1997)
• ethnic minority health (1999, 2004)
• older people - including care home residents (2000)
• fruit and vegetable consumption (2001)
• children, young people, and maternal health
Examination components
• Aside from core variables, measurements vary
year on year, eg:
• Blood samples (eg glycosylated Hb, ferritin,
gamma GT, cholesterol, fibrinogen, serum
cotinine, IgE, house dust mite IgE, lead, creactive protein, triglycerides, glucose,)
• Spot urine samples
• Salivary cotinine
• Lung function tests
• Grip strength/balance [older persons]
Monitoring & Reporting
HSfE – Parliamentary Questions
• Rosie Cooper: To ask the Secretary of State for Health what
estimate she has made of the percentage of adults in
West Lancashire with high cholesterol levels. [64112]
• Mr. Byrne: The information is not available in the format requested. Data
on cholesterol levels are available from the Health Survey for England
(HSE). The most recent data available on cholesterol are for
2003, as this is the last year where the HSE focused on
cardiovascular disease.
• The results in the table show the mean total cholesterol levels for
adults for England and the North West Government Office Region,
broken down by gender for 2003.
HSfE - Source for national
& international databases
• The WHO Global InfoBase is a data warehouse that
collects, stores and displays information on chronic
diseases and their risk factors for all WHO member
• Blood Pressure: Raised blood pressure causes stroke
and heart disease
• Cholesterol: High cholesterol levels increase the risk of
coronary heart disease
• Overweight & Obesity: (BMI)
National Service Frameworks
National service frameworks (NSFs) are long term
strategies for improving specific areas of care. They set
national standards, identify key interventions and put
in place agreed time scales for implementation
Blood pressure
Coronary heart disease
Long term conditions
Long term neurological conditions
Mental health
Health examination data feeds into development and
monitoring of these NSFs.
HSfE- health inequalities
HSfE- health inequalities
Health Inequalities
Health Survey for England reports on data by:
• Age
• Gender
• Area (including “Spearhead” areas)
• Equivalised household income
• [Social class/NS-SEC]
• [Ethnicity]
Target setting – eg Health of the Nation, Our
Healthier Nation
Target monitoring:
BMJ 1996 (8 June)
Britain is failing to meet targets on reducing obesity
17% of men (19% of women) had a systolic blood pressure over 160 mm Hg or
were being treated for hypertension.
A drop in the average systolic blood pressure from 139 mm Hg to 136 mm Hg
was found in 16 to 64 year olds. These figures suggest a downward trend
towards the government's target of an average systolic pressure of 133 mm Hg
by the year 2005.
But future surveys are needed to see whether the trend will continue.
Driver for action
Improved hypertension and management and control: Results
From the Health Survey for England 1998, Primatesta et al
CMO recommendations
CMO recommendations (2)
Quantifying impacts
Quantifying impact of
CHD: Estimating the impact of changes in risk factors
(McPherson Klim, Britton Annie, Causer Louise)
main risk factors for CHD: cholesterol, physical activity,
blood pressure, smoking and obesity
estimates the relative impact that changes to these risk
factors may have on the number of cases and deaths
from the disease in England.
each risk factor is looked at individually and the
percentage reduction in coronary heart disease that
could be achieved in the population as a whole, and
where possible, among individual groups is assessed
Planning for the future
Health Poverty Index
HPI – “health capital”
Individuals potential for health across the life
• Need to provide small area estimates
• Modelled estimates produced:
Blood pressure
Low birth weight (for infants)
Prevalence modelling
Models that show the expected prevalence of
disease in given geographies and user-defined
Coronary Heart Disease
Chronic Obstructive Pulmonary Disease
Chronic Kidney Disease
Prevalence modelling (2)
• Disease prevalence models to support 2007-8 Primary Care
Trust (PCT) “Local Delivery Plans (LDPs)”
• Association of Public Health Observatories was commissioned by the
DH to produce PCT level prevalence estimates for hypertension
and coronary heart disease. These estimates are based on two
separate models derived from the Health Survey for England (HSE).
• Models are only intended to give indicative expected
prevalence and are part of ongoing work to produce
refined estimates.
• Comparisons of national prevalence data from the HSE and recorded
prevalence from the Quality and Outcomes Framework (QOF)
suggest that there is considerable under-diagnosis (in terms of IT
system recording) of risk factors and diseases.
Prevalence modelling – COPD
• The overall prevalence of COPD in England is estimated as 1.3
million, of whom as many as 600,000 people may be unaware of
their diagnosis, therefore missing the opportunity of benefiting from
early interventions.
• importance of active case finding
• model can be used to identify areas with a high level of unmet
needs, i.e. with a high proportion of undiagnosed disease, where the
benefits of case finding would be optimised.
• This strategy may also have an impact on reducing health
inequalities, due to the socio-economic class gradient in COPD
• The model should be validated, and case-finding strategies using
the model should be evaluated for their cost-effectiveness.
[Luis C Nacul, Michael Soljak, and Tom Meade September 2007]
Prevalence modelling – COPD
• A mathematical model based on HSfE developed
• Logistic regression analysis was used to investigate and
choose risk factors for inclusion in the model and to
derive the prevalence estimates based on the strength of
association between selected risk factors and the
outcome COPD.
• The model allows the prevalence to be estimated in
populations at national level and also at regional and
large local areas, based on their compositions
according to age, sex, smoking and ethnicity, and on area
degrees of urbanisation and deprivation.
Prevalence modelling – COPD
A main advantage of the HSfE model is that it is:
– based on high quality data
– from a large representative sample of the population,
– uses standard and specific diagnostic criteria for
– which is based on lung function rather than symptoms.
Prevalence modelling – COPD
• estimated the overall prevalence of COPD in England as
3.1% in people over 15 years old and 5.3% in those over
45 years old.
• model illustrates the huge inequalities in the prevalence
of COPD across England (extreme risks in black men in urban
deprived areas in one end of the risk spectrum, and Asian women in the
lowest deprived rural areas, in the opposite end, between whom the risk of
COPD varies 7-fold on average)
• Thus simpler models that do not take into account such
variations in prevalence across population groups, would
be inappropriate for local use.
Prevalence modelling – COPD
• “We believe that compared to previous models and
prevalence estimates, the HSfE-Model offers the most
reliable estimates for England and the United Kingdom.
• It recognises deprivation, urban living and ethnicity as
independent risk factors for COPD, which are taken into
account in the estimates derived, in addition to smoking,
age and gender.
• The model gives prevalence estimates for areas of
varying sizes, including large populations at local level,
however, the precision of the estimates will be higher for
larger areas.”
[Luis C Nacul, Michael Soljak, and Tom Meade September 2007]
HSfE- other uses: eg
• Project: Ethnic differences in hypertension, diabetes,
dyslipidemia and the role of contextual factors: A comparative
analysis between the Netherlands (the SUNSET study), and the UK
studies (the Newcastle Heart Study and Health Survey for
• Cardiovascular disease (CVD) is a major public health burden and
the rates are higher in some minority populations than in White
populations. The causes of the excess risks are incompletely
understood and pose a high level scientific challenge. International
comparisons provide a good opportunity to gain more insight into
the role of contextual factors (i.e. lifestyle, health care and
socio-economic factors) in ethnic disparities in health.
HSfE- other uses
HSfE- examples of uses (1)
– Monitoring (general)/Surveillance
– National/international collations/databases
– Targets
Health inequalities
CMO report – highlighting issues
Underpinning policy development National
Service Frameworks –
HSfE- examples of uses (2)
• Health Poverty Index – modelled variables
• National prevalence models
– All
• Risk factor models
• Future scenarios
• Research
Final reflections (1)
“In England and Wales, the CHD NSF, NHS Plan, and CHD Information
Strategy now explicitly recognise the huge importance of disease
Monitoring and service evaluation. All have made a number of specific
and sensible recommendations. However, at present over 99% of the
£2 billion NHS CHD budget is spent on medical interventions,
particularly revascularisation. Less than 1% is currently spent
on the monitoring of CHD. These are inadequate resources for even
basic information strategy or information technology.”
Final reflections (2)
• Examination component gives us
critical information on key aspects of
health status and health determinants
• The examination component may be
considered a relatively expensive
component of the survey programme
but it is essential for informed
(“evidence-based”) policy-making
Final reflections (3)
• Major hurdle: getting programme started
• Monitoring tool
– Frequency of surveys [1y;2y;5y] – monitoring and practical issues
– Timeliness of data (headline figures)
Costs & opportunity costs
Added value of combining information
Relevance – eg to political agenda
Evolution vs ongoing monitoring
Standardised measurements vs GP systems
Local perspective
EU information