Evolution of the scientific literature on drug delivery: A 1974-2015 bibliometric study.

This study charts the growth of the drug delivery literature published during 1974-2015 from journals indexed in the Science Citation Index Expanded database. The growth of publications on drug delivery paralleled the total scientific publications for three decades (1974-2003); however, from 2004 to 2015 it exploded fourfold, while the total increased only 1.75 fold. Industrialized countries (USA, UK, Germany, Japan, Italy, France and Canada) were the most prolific during the first decades, but in 2014-2015 China, India and South Korea ranked 1st, 3rd and 4th respectively among the productive countries. The number of participating countries increased fivefold (from 19 to 96). During the last 15years, the journals targeted by drug delivery research increased nearly 2.4 fold (416 to 1001) and three journals (Journal of Controlled Release, Advanced Drug Delivery Reviews, and International Journal of Pharmaceutics) published nearly one-fifth of the drug delivery research in 2014-2015.