In due course, Nightingale’s statistical studies spearheaded a revolution in army hospitals, because the Royal Commission’s report led to the establishment of an Army Medical School and a system of collecting medical records. In turn, this resulted in a careful monitoring of which conditions and treatments did and did not benefit patients.
Today, Florence Nightingale is best known as the founder of modern nursing, having established a curriculum and training college for nurses. However, it can be argued that her lifelong campaigning for health reforms based on statistical evidence had an even more significant impact on healthcare. She was elected the first female member of the Royal Statistical Society in 1858, and went on to become an honorary member of the American Statistical Association.
Nightingale’s passion for statistics enabled her to persuade the government of the importance of a whole series of health reforms. For example, many people had argued that training nurses was a waste of time, because patients cared for by trained nurses actually had a higher mortality rate than those treated by untrained staff. Nightingale, however, pointed out that this was only because more serious cases were being sent to those wards with trained nurses. If the intention is to compare the results from two groups, then it is essential (as discussed earlier) to assign patients randomly to the two groups. Sure enough, when Nightingale set up trials in which patients were randomly assigned to trained and untrained nurses, it became clear that the cohort of patients treated by trained nurses fared much better than their counterparts in wards with untrained nurses. Furthermore, Nightingale used statistics to show that home births were safer than hospital births, presumably because British homes were cleaner than Victorian hospitals. Her interests also ranged overseas, because she also used mathematics to study the influence of sanitation on healthcare in rural India.
And throughout her long career, Nightingale’s commitment to working with soldiers never waned. In one of her later studies, she observed that soldiers based in Britain in peacetime had an annual mortality rate of 20 per 1,000, nearly twice that of civilians, which she suspected was due to poor conditions in their barracks. She calculated the death toll across the whole British army due to poor accommodation and then made a comment that highlighted how this was such a needless waste of young lives: ‘You might as well take 1,100 men every year out upon Salisbury Plain and shoot them.’
The lesson to be learned from Florence Nightingale’s medical triumphs is that scientific testing is not just the best way to establish truth in medicine, but it is also the best mechanism for having that truth recognized. The results from scientific tests are so powerful that they even enable a relative unknown such as Nightingale — a young woman, not part of the establishment, without a great reputation — to prove that she is right and that those in power are wrong. Without medical testing, lone visionaries such as Nightingale would be ignored, while doctors would continue to operate according to a corrupt body of medical knowledge based merely on tradition, dogma, fashion, politics, marketing and anecdote.
A stroke of genius
Before applying an evidence-based approach to evaluating alternative medicine, it is worth re-emphasizing that it provides extraordinarily powerful and persuasive conclusions. Indeed, it is not just the medical establishment that has to tug its forelock in the face of evidence-based medicine, because governments can also be forced to change their policies and corporations may have to alter their products according to what the scientific evidence shows. One final story illustrates exactly how scientific evidence can make the world sit up, listen and act regarding health issues — it concerns the research that dramatically revealed the previously unknown dangers of smoking.
This research was conducted by Sir Austin Bradford Hill and Sir Richard Doll, who had curiously mirrored each other in their backgrounds. Hill had wanted to follow in his father’s footsteps and become a doctor, but a bout of tuberculosis made this impossible, so instead he pursued a more mathematical career. Doll’s ambition was to study mathematics at Cambridge, but he got drunk on three pints of Trinity Audit Ale (8 per cent alcohol) the night before his entrance exam and underperformed, so instead he pursued a career in medicine. The result was a pair of men with strong interests in both healthcare and statistics.
Hill’s career had involved research into a wide variety of health issues. In the 1940s, for instance, he demonstrated a link between arsenic and cancer in chemical workers by examining death certificates, and he went on to prove that rubella during pregnancy could lead to deformities in babies. He also conducted important research into the effectiveness of antibiotics against tuberculosis, the disease that had ended his hopes of becoming a doctor. Then, in 1948, Hill’s interest turned towards lung cancer, because there had been a sixfold increase in cases of the disease in just two decades. Experts were divided as to what was behind this health crisis, with some of them dismissing it as a consequence of better diagnosis, while others suggested that lung cancer was being triggered by industrial pollution, car fumes or perhaps smoking.
With no consensus in sight, Hill teamed up with Doll and decided to investigate one of the proposed causes of lung cancer, namely smoking. However, they faced an obvious problem — they could not conduct a randomized clinical trial in this particular context. For instance, it would have been unethical, impractical and pointless to take 100 teenagers, persuade half of them to smoke for a week, and then look for signs of lung cancer.
Instead, Hill and Doll decided that it would be necessary to devise a prospective cohort study or an observational study, which means that a group of healthy individuals is initially identified and then their subsequent health is monitored while they carry on their day-to-day lives. This is a much less interventionist approach than a randomized clinical trial, which is why a prospective cohort study is preferable for exploring long-term health issues.
To spot any link between smoking and lung cancer in their prospective cohort study, Hill and Doll worked out that they would need to recruit volunteers who fulfilled three important criteria. First, the participants had to be established smokers or vehement non-smokers, because this increased the likelihood that the pattern of behaviour of any individual would continue throughout the study, which would last several years. Second, the participants had to be reliable and dedicated, inasmuch as they would have to commit to the project and submit regular updates on their health and smoking habits during the course of the prospective cohort study. Third, in order to control for other factors, it would help if all the participants were similar in terms of their backgrounds, income and working conditions. Also, the number of participants had to be large, possibly several thousand, because this would lead to more accurate conclusions.
Finding a group of participants that met these demanding requirements was not a trivial task, but Hill eventually thought of a solution while playing golf. This prompted his friend Dr Wynne Griffith to comment, ‘I don’t know what kind of golfer he [is], but that was a stroke of genius.’ Hill’s brilliant idea was to use doctors as his guinea pigs. Doctors fitted the bill perfectly: there were lots of them, many were heavy smokers, they were perfectly able to monitor their health and report back, and they were a relatively homogenous subset of the population.