Alexander studied psychology at the Autonomous University of Barcelona, focusing on statistics and specialising during his master's degree and PhD in systematic reviews. After a four year long post-doctoral fellowship at McMaster University doing meta-analyses in the area of obstetrics, his interest in topics related to developing countries brought him to the Medical Research Council Unit in The Gambia (at the LSHTM), where he worked as a statistician for two years before joining the MRC TB multimorbidity team under the supervision of Najma Siddiqi.
From a research methods perspective, Alexander is interested in systematic reviews and machine learning, and is waiting for an opportunity to learn about geographical information systems. In terms of research topics, Alexander is interested in risk of bias (in particular industry bias/ bias due to conflicts of interest), pneumonia in children under five, and TB and multimorbidity.