Complex sentence: He was the inventor of the concept of the intelligence quotient, or IQ, later used by Lewis Terman and other researchers in the development of the first IQ tests, based on the work of Alfred Binet.
Split into simpler sentences: He was the inventor of the concept of the intelligence quotient, later coined by Lewis Terman as IQ. Other researchers in the development of the first IQ tests, based on the work of Alfred Binet.