Sources Of Health & Demographic Information Flashcards
What is demography?
The study of the size, structure, dispersement + development of human populations
Demography is used to establish reliable statistics on:
- Population size + distribution
- Birth + death rates
- Life expectancy
- Migration
What are the 2 census’?
Birth registration
Death registration
What is a census?
The simultaneous recording of demographic data by the government at a particular time pertaining to all the persons who live in a particular territory (describes both households + people)
What is the history + process for UK census?
Office for National Statistics (ONS) in England + Wales
Every 10 yrs since 1841 (legally)
Low enumeration groups
Accuracy - Census Coverage/Quality Survey (interviews)
Move to administrate data/online > 2021
What data is included in the UK census?
Demographic (age/sex breakdown) Cultural characteristics (ethnicity/religion) Material deprivation (employment/home ownership/overcrowding/car access/lone parents/lone pensioners) Health (general, long-term illness, unpaid care) Workplace + journey to work
What areas are included in the census and who collects the data?
Output areas
Super output areas
Electoral wards
Collected by:
Local authorities
Clinical commissioning groups
How can you assess the quality of health information?
Completeness Accuracy Representativeness/relevance Timeliness Accessibility
What are the strengths of the UK census?
C - 98% completeness
A -Forms, coverage + quality surveys are checked
R - Data available for different levels (200 people to a country)
T -
A - Via website + local councils
What are the weaknesses of the UK census?
C - low enumeration of some groups
A - self reported i.e. religion as ‘Jedi’
R - Low enumeration of some groups
T - 10 years so takes time to release
A - individual returns confidential 100 yr
Why is the data in the UK census of value to health workers?
Population size + structure i.e. young, old + ethnic minorities -> service needs Base population (denominator) -> rates Measures of material deprivation -> identify + target inequalities
How are births registered?
Birth notification by birth attendant within 36 hrs to health authority + birth registration by parents within 42 days -> local registrar for births, marriages + deaths -> ONS (birth statistics)
What are the 3 measures of fertility?
- Crude birth rate (live births/1000 popl.)
- General fertility rate (live births/1000 women 15-44 yrs)
- Total fertility rate (no. of children that would be born to a woman if she were to live to end of childbearing years + bear children in accordance with age-specific fertility rates i.e. 2.1 births/woman in Britain)
What are the 3 factors that affect total fertility rate?
- Delay in childbearing to older ages
- Lower completed family size
- Population structure
How are deaths registered?
Medical certificate of cause of death issued by Dr (fact of death, age + place & death info) + referral to coroner for coroners certificate -> death registration by informant within 5 days to local registrar for births, marriages + deaths -> ONS (mortality stats; coded using ICD10)
What are the 3 underlying causes of death that are included in a death certificate?
- Disease or condition DIRECTLY leading to death
- Other disease or condition, if any, leading to 1 (INTERMEDIATE cause of death)
- Other disease or condition, if any, leading to 2 (UNDERLYING cause of death)
Define the underlying cause of death.
The disease or injury which initiated the train of morbid events leading directly to death
OR
The circumstances of the accident or violence which produced the fatal injury
How is the underlying cause of death used?
Used in mortality statistics as preventing the first disease/injury will result in the greatest population health gain
A patient with primary squamous cell carcinoma of the lung died from an intracerebral haemorrhage, which was caused by cerebral metastases from the primary. What are the 3 types/causes of death?
Direct cause: Intracerebral haemorrhage
Intermediate cause: Cerebral metastases
Underlying cause: Carcinoma
What are the strengths of the mortality data?
Complete coverage in UK (for births too)Important information of health of population
What are the weaknesses of the mortality data?
Accuracy? e.g. underlying cause of death subject to diagnostic uncertainty, coding issues + variable quality
Ethnicity not collected
Derivation of socio-economic status (posthumous inflation of stats)
Why are population estimates + projections needed?
For planning services/resource allocation
In the past: understand what has been happening to population
The present: to make sense of present activity
In the future: to predict what is going to change
What are population estimates?
Estimate of population size + structure between census’
Applies what is known on births/deaths/migration to present i.e. census baseline + births - deaths +/- migration
What are the strengths of population estimates?
More up to date than the census
More accurate than projections
What are the weaknesses of population estimates?
Less reliable with time from census
Poor information of migration
Says nothing about the future
What are population projections?
Forecasts future population size + structure
Based on assumptions about mortality, fertility + migration
What are the strengths of population projections?
Can be used for longer term planning
What are the weaknesses of population projections?
Less accurate the further ahead
Unforeseen changes of past trends can invalidate projections
What does the population projection from 2016-2014 show?
Projected increase in dementia driven by ageing of population
Why is assessment of a populations health complex?
Need range of health information
No one source of health data is perfect
Many sources of data
What are the 3 aspects of morbidity data?
- Cancer registration system
- NHS data
- Notifications of infectious diseases
What is the cancer registration system?
National Cancer Registration and Analysis Service (NCRAS): PHE
Cancer diagnosis triggers registration -> sends core dataset i.e. personal details, diagnosis, treatment + outcomes
What are the uses of the cancer registration system?
Monitor cancer rates
Evaluate/improve cancer treatment
Evaluation of screening programmes
Aiding cancer research
What are the strengths + weakness of the cancer registration system?
Strengths: detailed information updated over time + record linkage to cancer deaths (ONS)
Weaknesses: Expensive + access is difficult due to confidentiality
What is NHS data? Give 2 examples.
Large amount of information about NHS activity is collected for administrative + clinical purposes e.g. Hospital Episode Statistics (HES) + Quality and Outcomes Framework (QoF)
What does Hospital Episode Statistics (HES) report information on?
All admissions, out-patient + A&E visits to NHS hospitals in England e.g. personal information (age, gender_, clinical info (diagnosis, operations), administrative data (date of admission, discharge) + geographical info (where treated + lives)
Who uses the Hospital Episode Statistics (HES)?
Commissioning organisations
Provider organisations
Researchers
What is the Hospital Episode Statistics (HES) used for?
Trends in NHS hospital activity
Supports local service planning
Health trends over time
Fair access to healthcare
What are the 2 main clinical classifications currently used in Hospital Episode Statistics (HES)?
ICD-10: describes conditions treated or investigated e.g. MI, fractured skull (used for coding mortality stats too)
OPCS-4: records details of operations e.g. hip replacement
What does ICD-10 stand for?
International Classification Of Diseases 10th revision
What does OPCS-4 stand for?
Classification of Surgical Operations and Procedures 4th revision
How many chapters does ICD-10 have?
22
What are the strengths of Hospital Episode Statistics (HES)?
Completeness: covers all hospital activity
Accuracy: standard codes used
Representative: routine national data
What are the weaknesses of Hospital Episode Statistics (HES)?
Accessibility: to individual data
What is the Quality and Outcomes Framework (QoF)?
Primary care data introduced in GP contract linked to GP payments, voluntary + ‘rewarding good practice’ to improve care
What 3 domains are points awarded to GPs in the Quality and Outcomes Framework (QoF)?
Clinical (19 areas) e.g. managing chronic diseases e.g. diabetes
Public health e.g. cardiovascular disease (primary prevention), BP, obesity 18+, smoking 15+ etc.
Public health i.e. additional services e.g. cervical screening, contraception
If a GP gets a higher number of Quality and Outcomes Framework (QoF) points, what is the reward?
Higher GP income (adjusted for caseload + casemix)
-> significant to NHS + significant incentive
Do NICE think that the Quality and Outcomes Framework (QoF) improves outcomes?
Info recording: definitely
Process: mostly yes
Intermediate outcomes: sometimes
Clinical outcomes: unclear
What affect has the Quality and Outcomes Framework (QoF) had on clinical outcomes?
Strong evidence that there was initial improvement but then fell back to pre-existing trends suggesting this is process driven
However, evidence that poorest performing practices have improved the most
What are the strengths of the Quality and Outcomes Framework (QoF)?
C - almost 100% response from GPs
A -
R - representative of all populations: data at surgery, CCG, national levels
T - updated annually so reasonably timely
A - accessible online
What are the weaknesses of the Quality and Outcomes Framework (QoF)?
C - excludes practices who do not participate
A - e.g. not sure how accurate/complete disease registers are for individuals practices
R - only get aggregated data for each practice i.e. no age/sex breakdown
T -
A - aggregated data only
How are notifiable infectious diseases surveyed?
Dr suspects a case -> notify local health protection team
OR
Lab identifies organism -> notify PHE
= PHE collates + produces national trends each week
What is the use of surveillance of infectious diseases?
Action to prevent further infection
Identify outbreak
Monitor trends
How many notifiable infectious diseases are there in England + Wales?
31
Give a few examples of notifiable infectious diseases.
Tuberculosis Meningococcal septicaemia Measles Viral haemorrhagic fever (VHF) i.e. Ebola Plague (Yersinia Pestis)
What are the strengths of notification of infectious diseases?
Timeliness: weekly report be PHE
Representative: routine national data
Linked to other data to improve accuracy e.g. lab reports
What are the weaknesses of notification of infectious diseases?
Poor/variable completeness for some diseases e.g. not all food poisoning notified because treated at home
Accuracy can be questionable due to diagnostic uncertainty as asked to notify ‘suspected’ cases (although increasingly linked to lab reports nowadays)
