pharmacoepidemiology

Pharmacoepidemiology is the study of the use and effects of medicines in large populations. It combines concepts from pharmacology and epidemiology to understand how drugs perform in real-world settings, complementing data from randomized controlled trials with observations from routine clinical practice.

Its aims include measuring drug safety and effectiveness, identifying adverse drug events, evaluating patterns of drug utilization, and informing regulatory decisions, clinical guidelines, and health policy.

Common study designs are observational in nature, such as cohort studies, case-control studies, case-cohort and self-controlled case series, and case-crossover designs. Analyses often rely on linked data from electronic health records, claims databases, patient registries, and spontaneous reporting systems. Methods to address bias include propensity score adjustment, instrumental variable analysis, and robust confounding control.

Applications include post-marketing surveillance, signal detection for new safety concerns, assessment of comparative effectiveness, risk-benefit analyses, and support for labeling changes and risk management plans.

Pharmacoepidemiology is distinct from pharmacovigilance, which emphasizes safety signals from spontaneous reports, whereas pharmacoepidemiology emphasizes estimation of effect in real-world populations using various data sources. Ethical considerations include privacy, data protection, and appropriate use of patient information; limitations include confounding, measurement error, and data quality.

The field matured in the wake of the thalidomide tragedy in the 1960s and the ensuing regulatory reforms that strengthened post-marketing safety monitoring.