How do we measure population aspects?

Size, composition, lifestyle, illness, disease, births, deaths, life expectancy

How does the population census work in the UK?

Carried out every 10 years since 1801. Statutory authority is Census Act 1920. Registrar General for each country has a duty for carrying out the census. In Scotland, the National Records of Scotland on behalf of Registrar General for Scotland.

What is in the census proposal?

sets out how questionnaires will be securely collected, processed & analysed to produce high-quality statistics. Seeking views on How 2022 Census outputs are used, Future requirements for statistics about Scotland’s housing, its people and their characteristics.

Who completes the census?

Head of household

What sort of things does it ask about?

address, type of building, number of rooms, tenure,presence of amenities (bath, shower, toilet, central heating), Number of people in household, DOB, Gender, Marital status, Usual address, Relationship to head of house, Country of birth, Ethnic group, Presence of long term illness, Health problems of handicap which limits activities, Employment, Education, Transportation, In Scotland ability to speak Gaelic

What are population estimates?

Completed annually between census points, uses census data as baseline, add births, subtract deaths & makes an allowance for migration

What are population projections?

attempts to project characteristics & size of population into the future – makes assumptions about fertility, mortality & migration

Information on medical certificate of cause of death includes what?

name, age ,date & place of death , cause of death – coded according to International Classification of Diseases (ICD-11). Must be completed within 8 days.

Measurements for calculating mortality rate -

Crude death rate, standardised mortality rate, infant mortality rate, perinatal mortality rate, stillbirth rate, life expectancy

Crude death rate

number of deaths/1000 population/year

Standardised mortality rate

compares mortality levels in different years, or for different sub- populations in the same year - takes account of differences in population structure such as age Ratio - observed to expected deaths, multiplied conventionally by 100

Infant mortality rate

number of deaths in first year of life/1000 live births

Perinatal mortality rate

number of stillbirths & deaths in first 7 days after birth/1000 births (live & stillborn)

Stillbirth rate

number of stillbirths/1000 births (live & stillborn)

Life expectancy

number of years a person could expect to live on average, based on mortality rates of the population in a given year

Sources for calculating morbidity rates -

Scottish health survey, scottish household survey (limited health data)

Scottish health survey

detailed picture of health of Scottish population in private households – 3 previous surveys 1995, 1998 & 2003 - running continuously from 2008 Aim - to estimate prevalence of a range of health conditions & to monitor progress towards Scottish health & dietary targets - interviews & potential follow up nurse visits (adults only) - 2024 4591 adult & 1986 children (0-15) interviewed

What does the scottish health survey record?

Biological data, prescribed medicines, food poisoning, stress, anxiety, depression, blood pressure, waist, hip, mid-upper arm circumference & arm length, also collect saliva & urine samples

What is the scottish household survey?

continuous survey based on a sample of general population in private residences in Scotland – first commissioned by Scottish Executive in 1998 to provide reliable & up-to-date information on the composition, characteristics & behaviour of Scottish households

What is epidemiology?

study of factors affecting health of populations & how diseases are distributed throughout populations

What does it involve?

Classifying diseases , Showing the scale of the problem , Showing the natural history & aetiology of the condition , Showing causation & association , Identifying risk

How do we classify diseases?

ICD-11 - International Classification of Diseases

Disease prevalence

all people in a defined population with a given disease, condition or characteristic at a given point in time or over a given time period – typically expressed as a percentage

Point prevalence

number of people in the defined population with a given disease/condition/characteristic at one given time point

Period prevalence

number of people in the defined population who have or have had a given disease/condition/characteristic at any time during a specified time period

Incidence

number of new cases of a disease/condition occurring in a population during a defined time interval, number of new cases over population at risk

Natural history & aetiology

Shows severity of the problem, ways in which people can be affected, Indicates if primary prevention is possible

Causation & association

Is there evidence that exposure to a particular environmental, lifestyle or socio-economic factor contributes to ill health

Identifying risks

Assessing the chance or probability of a disease or condition occurring, Through the use of case control & cohort studies (epidemiological methods), risk & prognostic factors can be determined

Epidemiological methods

Observational studies, Disease surveillance

Types of observational studies

Cohort studies (longitudinal or prospective), Case control studies, Prevalence (cross-sectional) studies, Incidence studies

Disease surveillance

collection, analysis & interpretation of data about who is most at risk, Many infectious disease have to be notified to the appropriate authorities, vital to the planning of healthcare services

Cohort studies (longitudinal or prospective)

a cohort is a population who have a characteristic in common (disease, treatment) & who are observed into the future to follow the course of the characteristic disadvantages – length of time that may be necessary to follow cohort & hence cost accrued, also necessity for large scale studies when outcome of interest occurs infrequently

Case control studies

group with condition of interest (cases) are compared with a similar group without condition (controls) to investigate past factors that may cause condition – always retrospective (looking back at past event)

Prevalence (cross-sectional) studies

survey a defined population to determine its disease status at or during a particular time

Incidence studies

proportion of a group free of a condition who develop it over a given time period - rate at which new cases arise in a population