The use of phototherapy was first discovered, accidentally, at Rochford Hospital in Essex, England, when a nurse, Sister Jean Ward, noticed that babies exposed to sunlight had reduced jaundice, and a pathologist, Dr. Perryman, who noticed that a vial of blood left in the sun had turned green. Drs Cremer, Richards and Dobbs put together these observations, leading to a landmark randomized clinical trial which was published in "Pediatrics" in 1968; it took another ten years for the practice to become established.