Virtual Clinical Trial Service Providers Market by Type of Therapeutic Area (Cardiovascular disorders, Infectious disorders, Metabolic disorders, Neurological disorders, Oncological disorders and Other disorders), End-Users (Small-sized players, Mid-sized players, Large players and Academia / Others), Phase of Development (Phase I, Phase II, Phase III and Phase IV), and Key Geographies (North America, Europe, Asia Pacific, and Rest of the World): Industry Trends and Global Forecasts, 2020-2050