Why "Decentralized" Doesn't Mean "Virtual" In Clinical Trials

What does decentralized mean? 

The word ‘decentralized,’ according to the Merriam-Webster dictionary is concisely defined as “the dispersion or distribution of functions and powers.” Furthermore, the Cambridge Dictionary states that “if a large company or organization decentralizes or is decentralized, its activities are moved from one large central place to several different, smaller places.” Note that the word itself does not inherently imply a means in which powers, services, functions, etc. are dispersed.