Post-market drug safety is a surveillance problem that clinical trials are structurally incapable of solving. Trials are too small, too short, and too selective to detect adverse events that occur in 1 in 1,000 patients, emerge after years of exposure, or concentrate in subpopulations excluded from enrolment. Pharmacovigilance begins where the trial ends – drawing on spontaneous reporting databases, electronic health records, insurance claims, and increasingly, digital patient-reported data.
My work in this domain focuses on disproportionality analysis of spontaneous adverse event reports – specifically the FDA Adverse Event Reporting System (FAERS) – alongside causal modelling frameworks that go beyond association to ask whether a signal is real, how strong it is relative to comparator drugs, and what the plausible mechanism is. The GLP-1 receptor agonist class has been a central focus: a drug class that went from niche diabetes therapy to one of the most prescribed medication classes in history within five years, with a post-market safety profile that is still being characterized.
Disproportionality analysis without causal thinking produces noise. The Reporting Odds Ratio and Proportional Reporting Ratio are screening tools, not evidence – they tell you where to look, not what you have found. My analyses pair signal detection with structured evaluation of confounding by indication, Weber effect bias, notoriety bias, and the plausibility of the proposed mechanism before a signal is characterized as a concern worth communicating.
Disproportionality Analysis (FAERS)
Calculating Reporting Odds Ratios and Proportional Reporting Ratios across drug–event pairs in the FDA Adverse Event Reporting System. Adjusted for concomitant medications, reporter type, and temporal reporting patterns to reduce Weber effect inflation and notoriety bias.
Causal Modelling for Drug Safety
Applying directed acyclic graphs to the pharmacovigilance setting – specifying confounders, mediators, and colliders in spontaneous reporting data where confounding by indication is nearly universal and cannot be ignored.
Active Surveillance in Claims Data
Using Medicare and commercial insurance claims to conduct active drug safety surveillance – cohort studies with new-user designs, active comparator selection, and high-dimensional propensity score adjustment to address channelling bias.
Signal Characterisation & Communication
Translating pharmacovigilance findings into structured safety communications for clinical and regulatory audiences – framing absolute risk, number needed to harm, and clinical context rather than reporting raw disproportionality statistics.