My first research focus is on the social determinants of infectious diseases, mainly on HIV and mainly in sub-Saharan-Africa. I have also researched the social patterning of tuberculosis and HIV in Brazil and bacterial sexually transmitted infections in the United States. 

My second area of focus is on social network and how social support and interaction can provide positive health outcomes: both the avoidance of unwanted infections such as HIV, and successful management of health conditions. This work has led me to start researching the health of older adults, particularly around dementia. 

My third area of focus is in field methods. This includes trialing methods to help respondents report sensitive data (e.g. sexual behaviour, history of abuse); we have used computer- and paper-based methods for this work. It also includes taking seriously the impact of interviewer behaviour on data collected, and on subsequent analytic outcomes. I have overseen several field studies in South Africa, Tanzania and Burkina Faso, and have also been involved in studies in Uganda and Zambia. For these studies we have used OpenDataKit, CommCare and REDCap.  

Analytically, I work in Stata, R and Python to appropriately manage dependencies between data, including hierarchical, spatial and network modelling. I used to work on the cost and cost-effectiveness of HIV services.