Studies like ours aim to unpack these deadly inequities, and data linkage allows us to analyse overlapping layers of disadvantage usually hidden from view.
Why is the project is so innovative?
The linkage, which was supported by the former Administrative Data Research Centre (ADRC) and the Economic and Social Research Council (ESRC) and the South London and Maudsley Trust Clinical Data Linkage Service (SLaM CDLS), is innovative in several ways.
First, it focuses specifically on mental health, drawing from the records of South London and Maudsley (SLaM) NHS Trust, one of Europe’s largest secondary mental health service providers. These records, available through the Clinical Records Interactive Search (CRIS), have had all identifiable information removed and have been ethically approved for researchers to access. This means that our data analysis can inform research and service improvements while keeping the identities of all services users protected and confidential.
Second, the project draws from a dense and diverse catchment area; only 38.7% of SLaM service users reported their ethnicity as ‘White’ in 2020-21. Many other surveys and cohort datasets are unable to produce sufficient data on ethnicity to draw significant conclusions. The SEP-MD study, however, includes enough records from patients identifying with minority ethnic groups to shed light on ethnic inequalities in mental health. SLaM’s catchment also includes several of the most deprived neighbourhoods in England, representing one extreme of the ‘social gradient’.
Third, the SEP-MD linkage makes use of the momentum generated by the pandemic. COVID-19 exposed stark ethnic and racial inequalities across health and social care, and the government’s pandemic response increased public awareness of the importance of national-level data collection. The King’s-ONS linkage was completed in early 2020, and enables a perspective on inequities prior to the pandemic. In the future we may consider refreshing the linkage to provide a perspective on changes since 2020.
Lastly, SEP-MD’s focus on social and economic predictors — based on data supplied by the Census on factors like employment — aligns with the interests and priorities of many patients and carers. From clinical experience and through consultations with mental health service user groups, the King’s researchers learned that employment, joblessness and household-level need – among other factors – shaped experiences of illness and access to care. Data linkage allows us to improve our understanding of these social conditions through quantitative metrics, while making sure these findings stay relevant to those affected by mental illness.