ABCs of EBVM

In the 18th century, sailors died from scurvy on a regular basis. In 1747, on Her Majesty’s Ship the Salisbury, young men under the care of Dr James Lind were dying, despite him following the current treatment recommendations for scurvy. At the time, the Royal College of Physicians recommended sulphuric acid, and the Admiralty recommended vinegar treatments. Dr Lind noted that the recommendations were all written by ‘experts’ who had never been on a long sea voyage.

Dr Lind reviewed the current evidence and ran his own treatment trial to see if he could find a treatment for scurvy. His trial compared the success of a concoction of sulphuric acid, vinegar, nutmeg, cider and seawater to a diet of two oranges and one lemon in different groups of sailors in similar stages of disease, who were otherwise sharing the same basic diet.

The sailors receiving the citrus fruit clearly improved more quickly than those ingesting the tasty sulphuric acid concoction, and Dr Lind had some evidence for a superior treatment. Following this clinical trial, the Admiralty made lemon juice compulsory for sailors, and deaths due to scurvy declined precipitously.

Dr Lind’s study is an excellent early example of the practice of EBM. As a clinician, Dr Lind posed the right, pertinent question about the disease, reviewed the relevant current evidence (literature), recognised the limitations of that evidence, and then executed a simple clinical trial, which led to a change in the way he treated his patients. Dr Lind also passed on his new knowledge by telling the Admiralty and the Royal College of Physicians, who then instituted change, saving many lives at sea.