Measuring Health And Disease

Question 1

Why measure the health of the population?

Answer 1

Find how common disease is (prevalence)
How many new cases (incidence)
Identify Longitudinal trends in disease
If intervention and policies o improve health are having an effect
Identify differences in disease patterns btw diff population groups/ locations
Organisation of service planning

Question 2

Institutions for information on measuring health status

Answer 2

Office for national statistics
NHS digital
Uk data service

Question 3

What data sources are used to measure health status

Answer 3

Death certificates
Census
Health survey of England
General lifestyle survey
Hospital episode statistics
GP research database
Health protection reports of notifiable infectious diseases
Cancer registration
National/ regional/ local audits or surveys

Question 4

What is a death certification

Answer 4

Legal requirement to register death - age, sex, occupation
DRS record cause of death and contributing diseases
International classification of disease codes

Question 5

What is a census

Answer 5

Tool for measuring population demographics
Every 10 years since 1851
Counts everyone in a household on a particular night
Age, gender, migration, education, martial status, health, housing condition, family structure, employees and travelling habits

Question 6

What are hospital episode statistics

Answer 6

Details of all admissions to NHS hospitals in England and all outpatient appointments
Started in 1989
Secures details on:
- Diagnosis and operations
- Age, gender, ethnicity
- Time waited and date of admission
- Geographical info on where treated
- Outcome: discharge home, care home, death

Question 7

What is a Clinical practice research datalink and what is it used for ?

Answer 7

Anonymised longitudinal data from 625 general practices serving 5 mill patients
Used for:
Clinical research planning
Studies of treatment patterns
Drug utilisation
Clinical epidemiology
Drug safety
Health outcomes
Health service planning

Question 8

Types of data sources used to compile graphs

Answer 8

Census
Death certificate
Hospital episode statistics
Clinical practice research datalink

Question 9

What is the health survey for England

Answer 9

• Annual population survey since 1990
• Contains questionnaire answers:
  Demographic info, smoking status, self reported info on health, illness, treatment, health service usage, blood and saliva sample analysis, height and weight
• Additional info on key theme each year (e.g. asthma)
• Freely available on line (via NHS digital)

Question 10

What is general lifestyle survey?

Answer 10

Sample from whole of England
Formerly called general household survey

• Demographic info about households, families and people
• Housing tenure and household accom
• Access to vehicles
• Employment
• Education
• Health and use of health services
• Smoking and drinking
• Family info, marriage. Cohabitation and fertility

Question 11

What is a “notifiable disease”?

Answer 11

Certain infectious disease notified by doctors
Laboratory results for some infectious diseases notified
Cancers registered in cancer registries and linked to mortality data

Question 12

Key methods of measuring health and disease

Answer 12

Birth and fertility rates
Incidence (how many new cases)
Prevalence (how common disease is)
Mortality rate (crude and standardised)

Question 13

Advantage of mortality data as a measure of population health

Answer 13

• Legal requirement in UK to register each death
• Little delay in collection of data
• International classification of disease ensures comparability
• Cheap source of health data

Question 14

Disadvantage of mortality data as a measure of population health

Answer 14

• Potential for error (diagnosis/ coding/ processing/ interpretation)
• Death may result from many diseases acting in conjunction
• Some diseases have high mortality rate & death occurs quickly/ some are long term, resource-intensive but rarely cause death

Question 15

How might we use mortality or mortality rates

Answer 15

Compare areas
- identify areas of poor health
- identify need for preventative services
- may raise hypothesis about cause of disease

Look at change over time

Question 16

What is direct standardisation

Answer 16

Direct: age specific death rates from a study population are applied to a standard population structure
Apply standard specific death rates to other populations

Question 17

Advantages of direct standardisation

Answer 17

• Can be used to compare disease rates across areas and time
• Can be used to assess the relative burden of different diseases in a population

Question 18

Disadvantages of direct standardisation

Answer 18

Requires age specific rates which not always available at a local level
Rates may not be stable for a small number of events

Question 19

What is indirect standardisation

Answer 19

Age specific rates from a standard population are applied to a study population structure (standardised mortality ratio)

Question 20

What is SMR

Answer 20

Standardised mortality ratio
Observed no. Of deaths for study pop/ expected no. Of deaths for study population

E.g. SMR of 150% or 1.5 means study population has .5 times as many deaths as you would expect

Question 21

Advantages of indirect standardisation

Answer 21

Doesn’t require local rates, only absolute number of events
Easier to interpret rates (always comparing to 1 or 100)

Question 22

Disadvantages of indirect standardisation

Answer 22

Areas cannot be directly compared
Doesn’t give an idea of actual burden of disease

Question 23

Pitfalls in interpreting health and disease

Answer 23

• Different criteria used to define the disease btw areas
• Not all cases of disease have been identified in each area
• Use of hospital data to describe disease or death in an area (omits people treated in GP or die in community)

Question 24

How socioeconomic deprivation relates to bad health

Answer 24

People living in areas with the highest socio-economic deprivation
- Lowest life expectancy at birth
- Highest death rates from most conditions (cardio, cancer)
- Higher rates of teenage pregnancy
- Higher levels of unhealthy lifestyle (smoking, diet, physical activity)

Question 25

Theories why health may be associated with socioeconomic deprivation

Answer 25

An artefact of measurement error
Social selection
Behavioural/ cultural
Psychological
Material/ structural conditions

Question 26

Definition of artefact theory

Answer 26

Observed associations are not genuine, but exists because of the ways in which we measure health ad deprivation

Question 27

Definition of social selection theory

Answer 27

Health determines socioeconomic status (if you are in poor health you are less likely to be able to work, and therefore are more ‘deprived’) rather that socio-economic status determining health

Question 28

Definition of behavioural/ cultural theory

Answer 28

People in deprived areas more likely to smoke, bad diet, less exercise

Question 29

Definition of psychological theory

Answer 29

The stress of working in poorly paid, low status job with little autonomy creates biological changes in the body which in turn create patho-physical changes

Question 30

Definition of material theory?

Answer 30

The directs effects of poverty

Question 31

More recent theories of why health may be associated with socioeconomic deprivation

Answer 31

Importance of area context
- physical environment, availability of goods and facilities social capital (the amount to which people are connected within their community through relationships and have a shared sense of identity)

Role of the life course
- Biological and social pathways between childhood and adulthood that accumulate risk for health, behaviours and social circumstances