The digital epidemiology of social media behaviour and mental wellbeing in the Avon Longitudinal Study of parents and children

There have been recent and startling rises in reported mental health difficulties, particularly in young adults. This means it is more crucial than ever to understand the origins of mental health and wellbeing to inform public health interventions and governmental policies that promote good mental health and prevent the far-reaching consequences of mental illness, an urgency recognised by both government and major research funders. Social media and other aspects of digital footprint have huge potential to facilitate the study of the causes of mental ill health through access to ecologically valid real time data on human behaviour. For example, the literature includes examples of automated methods for the detection of mental health conditions such as depression, Post-Traumatic Stress Disorder, suicidal ideation and Seasonal Affective Disorder. These measurements from social media have the potential to complement traditional questionnaire and diagnostic interview measures of these dimensions and disorders because they are based on large numbers of real social interactions and do not rely on retrospective recall or introspection.

Validating these digital phenotyping approaches against ground truth is key to realising this potential. However, participants in social media research are usually unknown, so it has been historically difficult to do this effectively, a limitation that has so far restricted the usefulness of research using social media and other aspects of the digital footprint. To overcome this, recent efforts have linked social media data in UK birth cohorts such as the Avon Longitudinal Study of Parents and Children (ALSPAC). Studying digital phenotypes in well characterised populations with established ground truth measures allows us to put social media analysis on a sound epidemiological footing.

This project aims to address limitations of earlier research by performing analysis using linked Twitter data for approximately 900 participants from ALSPAC. These data will be used to explore associations between Twitter behaviours (e.g. time of day when tweeting, language used in tweets, interactions with other users) and mental health and well-being. Where possible, we will use state-of-the-art approaches to make directional causal inferences about these relationships. Methodologically, this will involve machine learning techniques including Natural Language Processing and causal inference methods such as Granger Causality and Mendelian Randomization.

This project could enhance research into the relationship between social media and mental health outcomes. This could enable exploration of the various proposed causal mechanisms between social media and mental health, and the identification of potentially harmful social media usage. This could inform the development of interventions aiming to modify social media behaviour. Furthermore, knowledge of these relationships could help improve the robusticity of machine learning models aiming to predict mental health status from behaviour on social media

This project has three main research questions:

1. What is the relationship between timing of Twitter activity and mental health outcomes?

2. What is the relationship between Twitter network characteristics and mental health outcomes?

3. What is the relationship between incoming Twitter content and mental health outcomes

Impact on Health and Care
The CDT primarily addresses the most pressing needs of nations such as the UK - namely the growth of expenditure on long term health conditions. These conditions (e.g. diabetes, depression, arthritis) cost the NHS over £70Bn a year (~70% of its budget). As our populations continue to age these illnesses threaten the nation's health and its finances.

Digital technologies transforming our world - from transport to relationships, from entertainment to finance - and there is consensus that digital solutions will have a huge role to play in health and care. Through the CDT's emphasis on multidisciplinarity, teamwork, design and responsible innovation, it will produce future leaders positioned to seize that opportunity.

Impact on the Economy
The UK has Europe's 2nd largest medical technology industry and a hugely strong track record in health, technology and societal research. It is very well-placed to develop digital health and care solutions that meet the needs of society through the creation of new businesses.

Achieving economic impact is more than a matter of technology. The CDT has therefore been designed to ensure that its graduates are team players with deep understanding of health and social care systems, good design and the social context within which a new technology is introduced.

Many multinationals have been keen to engage the CDT (e.g. Microsoft, AstraZeneca, Lilly, Biogen, Arm, Huawei ) and part of the Director's role will be to position the UK as a destination for inwards investment in Digital Health. CDT partners collectively employ nearly 1,000,000 people worldwide and are easily in a position to create thousands of jobs in the UK.

The connection to CDT research will strongly benefit UK enterprises such as System C and Babylon, along with smaller companies such as Ayuda Heuristics and Evolyst.

Impact on the Public
When new technologies are proposed to collect and analyse highly personal health data, and are potentially involved in life or death decisions, it is vital that the public are given a voice. The team's experience is that listening to the public makes research better, however involving a full spectrum of the community in research also has benefits to those communities; it can be empowering, it can support the personal development of individuals within communities who may have little awareness of higher education and it can catalyse community groups to come together around key health and care issues.

Policy Makers
From the team's conversations with the senior leadership of the NHS, local leaders of health and social care transformation (see letters from NHS and Bristol City Council) and national reports, it is very apparent that digital solutions are seen as vital to the delivery of health and care. The research of the CDT can inform policy makers about the likely impact of new technology on future services.

Partner organisation Care & Repair will disseminate research findings around independent living and have a track record of translating academic research into changes in practice and policy.

Carers UK represent the role of informal carers, such as family members, in health and social care. They have a strong voice in policy development in the UK and are well-placed to disseminate the CDTs research to policy makers.

STEM Education
It has been shown that outreach for school age children around STEM topics can improve engagement in STEM topics at school. However female entry into STEM at University level remains dramatically lower than males; the reverse being true for health and life sciences. The CDT outreach leverages this fact to focus STEM outreach activities on digital health and care, which can encourage young women into computer science and impact on the next generation of women in higher education.

For academic impact see "Academic Beneficiaries" section.