3B sickness and health Flashcards
Routinely recorded mortality data: STATS19 (information, collection, uses, strengths and weaknesses)
INFORMATION
- injury or deaths from road traffic collisions
COLLECTION
- any RTC involving personal injury is recorded at the time by the police on a STATS19 form
- forms are collated by police and data is sent to department for transport who adds info to National Road Casualty Database
USES
- gives an indication of mortality from RTCs
- can be liked to data from A+E on injuries secondary to RTCs
STRENGTHS
- contains more information on type of vehicles etc than A+E reports
- may include incidents that did not present to ED
WEAKNESSES
- police do not attend all RTCs
- may be differences between how police and health services rate morbidity
Routinely recorded mortality data; give 2 sources of UK routinely recorded mortality data
- death certificates/ death registrations
- STATS19 (data on mortality secondary to RTC)
Routinely recorded mortality data: describe data from death certificates/ death registration and its strengths and weaknesses
- collated by ONS
INFORMATION
- cause of death and contributory factors
- place of death and time/date of death
- demographics (name, dob, address)
- place of birth
-occupation
-spouse/civil partner
COLLECTION,CODING AND ANALYSIS
- deaths have to be registered within 5 days
- deaths must be registered before a funeral can occur
- cause of death is coded by ONS using ICD-10 codes
- data is published annually by ONS
USES
- calculating life expectancies
- comparing regions and trends over time
- health needs assessment for serious conditions
STRENGTHS
- complete
- timely
- relatively accurate
- coding accuracy tends to be good as coded centrally by ONS
WEAKNESSES
- accuracy of cause of death less good for older people with multiple co-morbidities
- data may not be accurate ie occupation due to occupational advancement (tendency to increase socioeconomic status of people who have died)
- may be problems comparing over time when switched from ICD-9 to ICD-10
Routine sources of morbidity data
PRIMARY CARE
- CQRS system
- clinical practice research datalink
SECONDARY CARE
- hospital episode statistics
SURVEYS
- Integrated household survey
- Health Survey for England
CONDITION SPECIFIC REGISTRIES AND DATASETS
Routinely recorded morbidity data: describe data from the CQRS system (description, collection, coding and analysis, uses, strengths and weaknesses)
DESCRIPTION
- system used in GP primarily to calculate GP payments
- collects data on GP practices and calculates payments based on
1. Quality and outcome framework indicators
2. nationally commissioned services
3. locally commissioned services
COLLECTION, CODIING AND ANALYSIS
- extracts from GP may be sent to CQRS via the GP extraction service or other electronic means
- payments are linked to evidence based indicators through Quality and outcomes framework
- CQRS is accessible to staff working in public health departments
USES
- payments to GPs based on services delivered and degree to which QoF indicators are met
- registers provide an estimate of disease prevalence
- useful when planning new services
STRENGTHS
- as system is used for calculating payment there is an incentive for GPs to ensure data accuracy and completeness
- relatively complete since most people are registered with GP
- many conditions are treated nearly exclusively in primary care
- QoF score provides an indication of the quality of care provided by the practice
WEAKNESSES
- primarily designed for collating information for payments not for collecting information on disease prevalence etc
- accuracy depends on coding by the GP
- cannot use QoF to compare practices as affected by list size and population characteristics
- QoF is voluntary although most practices participate.
What are quality outcome framework indicators?
The quality outcome framework is a voluntary annual incentive and reward scheme for all GPs.
Practices score points for their level of achievement against certain indicators.
Routinely recorded morbidity data: describe data from the Clinical Practice Research Datalink (description, collection, coding and analysis, uses, strengths and weaknesses)
INFORMATION
clinical practice research datalink collates data from primary and secondary care, including the following
1. Data from GP electronic records
2. HES
3. primary and secondary care prescribing data
4. Mortality data
5. Disease registers
COLLECTION, CODING AND ANALYSIS
- data is coded differently in each of these datasets but it can be linked via NHS number
USES
- pseudonymous data is provided for research purposes
STRENGTHS
- linked data from multiple sources for a large number of patients
- longitudinal data primary care data available
- primary care data also includes lifestyle information (ie smoking)
WEAKNESSES
- data from many of these sources is incomplete
- not all GP practices participate
- to access data requires payment
Routinely recorded morbidity data: describe data from HES (description, collection, coding and analysis, uses, strengths and weaknesses)
INFORMATION
-Information is recorded from all hospital admissions including:
1. age, DOB, postcode, ethnicity
2. start and end date of admission, ward
3. Diagnosis, investigations, and procedures
- a limited amount of information is also recorded for outpatient appointments and A+E attendances
COLLECTION, CODING AND ANALYSIS
- hospital episodes are coded locally by clinical coders (not clinicians) who use ICD10 codes and OPCS4 (classification for interventions and procedures)
- data collected monthly as part of mandatory submission by hospitals
- data is then
1. sent to Secondary Uses Services who provide data to trusted organisations ie for commissioning
2. Cleaned and published in HES dataset
USES
- Used for commissioners to pay providers
- used to analyse hospital usage and waiting time
- assess quality of care and outcomes
- estimate health needs for conditions primarily managed in secondary care
STRENGTHS
- relatively complete (hospitals must submit in order to be paid)
- timely (submitted monthly)
- Can be linked to mortality data to generate stats that link episode to outcome at the individual level
WEAKNESSESS
-accuracy depends on medical notes completeness and the clinical coder
- Variable completeness
- relates to episodes not patients (may overestimate need if one patient has multiple admissions)
- only useful for conditions that are generally admitted to hospital
- only NHS data (not private hospitals)
Routinely recorded morbidity data: Integrated household survey
Integrated household survey combines:
- General Lifestyle Survey
- English Housing Survey
- Living Costs and Food Survey
and others!
- conducted annually by ONS
- 200 000 households
- generates data on:
- economic acitivity
- education
- alcohol consumption
- smoking
- illnesses
- consultations with healthcare professionals
Routinely recorded morbidity data: health survey for England
- Annual survey
- conducted by national centre for social research and UCL
- covers around 6000 households
- involves an:
1. interview (smoking, alcohol and other questions)
2. examination by nurse (height, weight, BP etc)
international health data sources: WHO Databases
- WHO regional departments maintain databases of health statistics
- ie European Health for All database
- collates statistics on demographics, health, risk factors and health services for countries in the WHO region
international health data sources: Global Burden of Disease Study
- commissioned by World Bank to compare burden of disease and risk factors across the world
- first in 1991
- now provides annual estimates of burden of disease for 371 disease and injuries across 204 countries from 1990 to present
international health data sources: Demographic and health surveys
- funded by USAID
- nationally representative household surveys in developing countries
- provide data on fertility, health etc
Bias
Systematic error that leads to a difference in how the comparison groups are selected, treated, measured or interpreted
Sources of bias in population data
- Response bias (selection bias)
- GP list size
- Occupational advancement
Sources of bias in population data: response bias
- type of selection bias
- particular problem with routine data collecting surveys
- even in the census certain groups are less likely to respond and therefore will be under-represented
Sources of bias in population data: GP list size
- GPs often delay or never remove patients who have died or moved away
- leads to a systematic error regarding estimations of population size and structure
- this can lead to an underestimation of service provision (ie vaccine uptake)
Sources of bias in population data: Occupational advancement (status inflation)
- there is a tendency for people to increase the socioeconomic status of people who are deceased when filling out surveys or death certificate information
- this is known as occupational advancement and can cause bias in social class data
Population data: what is artefact
- Spurious differences between and observed population characteristic and the actual population characteristic
Population data: give 3 examples of when artefact can arise
CHANGES IN CLASSIFICATION
ie when ONS changed from coding mortality data using ICD-9 to ICD-10. This made comparing mortality data from before and after the change challenging
CHANGES IN QUESTIONS OR POSSIBLE RESPONSES
ie when the census included ‘mixed’ as an ethnic option
CHANGES IN GEOGRAPHICAL SUBDIVISIONS ie when the census moved from electoral ward to output areas in 2001
Methods of classification of disease: the international classification of disease - what is it
- one of the WHO family of classifications
- Provides a common language for reporting, monitoring and recording diseases
- primarily an international standard classification for mortality statistics
- revised every 10-20 years
- it is problematic to translate codes between revisions so in the cross over period dual coding should be used