By the turn of the century, physiological, pharmaceutical, forensic, public health, and microbiological laboratories were in existence. The use and number of analytes found in the blood for clinical diagnosis and treatment was expanding. This is evidenced by the fact that in 1900 Dr. Otto Folin became, in its modern sense, the first full-time biochemist in the United States. In 1908 Todd and Sanford published the first edition of their book Diagnosis by Laboratory Methods. In addition to procedures for laboratory testing, the manual described general techniques for obtaining blood by venipuncture and skin stick. By the 1920s, the use of venipuncture for diagnostic testing had become widespread. The term phlebotomy took on a whole new meaning.
Image courtesy of Wikimedia Commons