GW4 BioMed2 MRC DTP PhD project: What are the biological mechanisms underlying the association between smoking, smoking cessation and mental health: a triangulation approach using machine learning, mendelian randomisation, and g-methods applied to multiple biological cohort studies

This project is one of a number that are in competition for funding from the GW4 BioMed2 MRC Doctoral Training Partnership which is offering up to 21 studentships for entry in September 2025.

The DTP brings together the Universities of Bath, Bristol, Cardiff and Exeter to develop the next generation of biomedical researchers. Students will have access to the combined research strengths, training expertise and resources of the four research-intensive universities. More information may be found on the DTP’s website.

Supervisory Team:

 Dr Gemma Taylor (lead), University of Bath, Department of Psychology

Dr Robyn Wootton, University of Bristol, School of Psychological Science

Professor Esther Walton, University of Bath, Department of Psychology

Professor Jack Bowden, University of Exeter, Medical School

The Project: 

Background: Smoking is the leading cause of preventable illness and death worldwide, with one in two smokers dying from smoking-related diseases unless they quit. While smoking prevalence has decreased overall, it remains disproportionately high among individuals with mental illness, contributing to health disparities. Research indicates smoking can cause mental ill-health and cessation improves mental health, though the biological pathways remain unclear. Preliminary evidence suggests smoking damages neurological and oxidative stress pathways, which may recover after cessation. Studies in this area often face challenges with confounders. This project proposes an innovative approach to explore the biological link between smoking, cessation, and mental health while addressing confounders using novel methods.

Aims and Method: The student will apply a triangulation approach to strengthen causal inference by comparing different methods with diverse biases. Using data from NHANES, IMAGEN, and UK Biobank, the student will compare estimates from traditional and advanced models, such as G-methods, machine learning, and Mendelian Randomization. This will provide robust conclusions and valuable training in various research techniques.

The student will have opportunities to lead both methodological and theoretical aspects, selecting variables, biomarkers, and outcomes, and shaping public involvement strategies.

The project comprises four main studies including a systematic review and meta-analysis of biological mechanisms linking smoking, cessation, and mental health, and cross-sectional and longitudinal analysis using data from multiple cohorts to examine the role of mediators in the relationship between smoking, cessation, and mental health.

International Impact: Findings will enhance our understanding of how smoking affects mental health and whether these effects are reversible. The results will inform individual-level interventions and public health policies, including targeted messaging on cessation benefits, as highlighted in the UK Government’s Khan Review, “Making Smoking Obsolete.”

Requirements:

Applicants must have obtained, or be expected to obtain, a First or Upper Second Class UK Honours degree, or the equivalent qualifications gained outside the UK, in an area appropriate to the skills requirements of the project. Applicants with a lower second class will only be considered if they also have a Master’s degree. Academic qualifications are considered alongside significant relevant non-academic experience.

Non-UK applicants will also be required to have met the English language entry requirements of the University of Bath.

Enquiries and Applications:

Informal enquiries are welcomed and should be directed to Dr Gemma Taylor - gmjm20@bath.ac.uk.

Formal applications must be submitted direct to the GW4 BioMed2 DTP using their online application form: GW4 BioMed MRC DTP - GW4 BioMed MRC DTP

A list of all available projects and guidance on how to apply may be found on the DTP’s website. You may apply for up to 2 projects.

APPLICATIONS CLOSE AT 17:00 (GMT) ON 4 NOVEMBER 2025.

IMPORTANT: You do NOT need to apply to the University of Bath at this stage – only those applicants who are successful in obtaining an offer of funding from the DTP will be required to submit an application for an offer of study from Bath.