The first clinical trial was conducted by the Scottish surgeon James Lind in the eighteenth century, when he tried to find a cure for scurvy. This disease was the worst enemy for fleets around the world, as everyone who embarked on a long journey at sea knew that he was going to be exposed to a fatal ailment that would rot his gums, cause sores to develop on the skin and leave him bedridden before ultimately causing his death.
In March 1747, Lind was assigned as surgeon to the HMS Salisbury. After eight weeks at sea, as scurvy began affecting the crew, Lind decided to test his idea that the rotting of the body caused by the disease could be prevented with acids. On May 20th, he divided 12 sick sailors into six pairs, each of whom was given a different supplement to his diet: cider, elixir of vitriol (dilute sulfuric acid), vinegar, sea water, two oranges and one lemon, or a purgative mixture.
As a result, only the two sailors who had the fruit got better, even though the orange and lemon supply ran out after six days. “The most sudden and visible beneficial effects were seen with the use of oranges and lemons,” wrote Lind in 1753 in his historic work A treatise of the Scurvy. “One of sailors who ate them was able to return to work after six days. The other had the highest degree of recovery from the condition and, since he was relatively fine, was assigned as the nurse for the rest.” From the results obtained, a few years later, lime juice was included in the crew’s diet.
The importance of Lind’s study is that he succeeded in controlling the experiment variables so that all subjects were under similar conditions – comparing equal to equal. According to his own account, the Scotsman chose patients with similar symptoms, kept them in the same place and provided them with a common diet, apart from the supplements, but without a control group.
In fact, others before Lind had already made advances in such approaches, starting with the Persian physician Al-Razi, who in the ninth century bled one group of patients and not the other to compare the results. A century earlier than Lind, others like the Flemish Jan Baptist van Helmont, the Englishman George Starkey, and the German Franz Anton Mesmer had already tested the comparison of equal to equal. The primitive design of those trials did not evolve until the nineteenth century with the introduction of double-blind treatment and the twentieth century with the inclusion of placebo.
Javier Yanes – Knowledge Window