What is the key purpose of pharmacovigilance?

Pharmacovigilance (abbreted PV or PhV), also known as Drug Safety, is the pharmacological science relating to the collection, detection, assessment, monitoring, and prevention of adverse effects with pharmaceutical products. Pharmacovigilance studies play a major role in this population, paicularly those studies that investigate functional impairment as an impoant adverse drug event. Ref: Hilmer S.N., Ford G.A. (2009). Chapter 8. General Principles of Pharmacology. In J.B. Halter, J.G. Ouslander, M.E. Tinetti, S. Studenski, K.P. High, S. Asthana (Eds), Hazzard's Geriatric Medicine and Gerontology, 6e.