FOI reference: FOI-2025-2512
You asked
I am reaching out regarding questions about mortality studies.
I am seeking to understand how these classifications are determined in the UK, specifically:
- How do the Office for National Statistics (ONS) and UK companies classify occupational codes for mortality rating purposes? Are there established standards or reference materials available?
- What is the basis for geographic variations in mortality rates? For instance, what factors contribute to differences between London and Scotland? Are these variations primarily driven by historical data, socioeconomic factors, or other variables?
- What additional parameters influence mortality rates in these analyses?
We said
Thank you for your request.
1. How are occupational classifications determined for mortality analysis?
The Office for National Statistics (ONS) uses the Standard Occupational Classification (SOC) system to categorise occupations in the UK. This system groups jobs based on factors like the nature of work, skill levels, and responsibilities. Occupations are classified into major, sub-major, and minor groups, ensuring a clear structure for comparing trends over time.
SOC is regularly updated to reflect changes in the labour market, including the emergence of new job sectors and shifts in the nature of work. For mortality studies, occupational classifications are essential for understanding potential links between different types of work and health outcomes. The ONS uses these classifications alongside the International Classification of Diseases (ICD-10) system to assign causes of death, providing a comprehensive view of mortality patterns across various occupations.
In addition, the National Statistics Socio-economic Classification (NS-SEC) system is sometimes used to assess individuals' social and economic status based on occupation and employment conditions. This provides further context for understanding how socio-economic factors may relate to mortality trends.
Reference Materials:
Standard Occupational Classification (SOC): For more information on the Standard Occupational Classification, refer to SOC 2020 - Office for National Statistics
NS-SEC Codes: Detailed information on socio-economic classifications can be found in The National Statistics Socio-economic classification (NS-SEC).
International Classification of Diseases (ICD): Further details on the International Classification of Diseases (ICD-10) are available on the International Classification of Diseases (ICD).
2. What factors contribute to geographic variations in mortality rates?
Geographic variations in mortality rates are influenced by several interconnected factors, including:
Socioeconomic Conditions: Differences in levels of deprivation across regions can contribute to variations in health outcomes. Areas with higher levels of poverty may experience different health challenges compared to more affluent areas.
Healthcare Access: The availability and quality of healthcare services can differ between regions. Urban areas tend to have more healthcare facilities and services, while rural areas may have fewer options and longer travel distances for care.
Lifestyle and Behavioural Factors: Regional differences in lifestyle, such as diet, smoking, alcohol consumption, and physical activity, can result in variations in health outcomes and mortality.
Environmental Factors: Environmental exposures, such as air pollution, water quality, and occupational risks, can vary by region and contribute to differences in health outcomes.
Historical and Cultural Factors: Historical and cultural influences in a region can shape long-term health trends. For example, regions with a history of industrialisation may experience different health challenges compared to areas with more diverse economies.
3. What additional parameters influence mortality rates in analyses?
In addition to occupation and geography, a range of other parameters can influence mortality rates, including:
Demographics: Age and gender are important factors, as mortality rates vary with age, and gender differences in health behaviours and risks can contribute to variations in mortality.
Comorbidities and Lifestyle Factors: The presence of chronic conditions like diabetes, hypertension, and obesity, along with lifestyle factors such as smoking, alcohol consumption, diet, and physical activity, can all contribute to differences in mortality rates.
Social Determinants of Health: Social factors, including education, employment status, and social support, can affect health outcomes and potentially influence mortality rates.
Environmental Exposures: Exposure to pollutants, hazardous substances, or other environmental factors, such as those linked to occupation or where people live, can influence health outcomes and mortality.
Public Health Policies: Government policies, including vaccination programmes, smoking bans, and health interventions, can contribute to variations in mortality trends over time.