Nightingale was convinced poor hygiene was to blame. Each night, she walked over six kilometres along the corridors of the wards, lamp in hand. Patients lay on filthy mattresses, rats hiding beneath, surrounded by walls covered in dirt. ‘The clothes of those men were swarming with lice,’ Nightingale noted, ‘as thick as the letters on a page of print.’ With her nurses, she set about cleaning up the wards. They made sure linens were laundered, bodies bathed, and walls washed. In March 1855, the British government sent a group of commissioners to the Crimea to tackle conditions in the hospitals. Whereas Nightingale had focused on hygiene, the commission worked on the buildings, improving ventilation and sewage systems.
Nightingale’s work earned her fame back at home. Shortly after returning to England in summer 1856, Queen Victoria invited her to come to Balmoral to discuss her experiences in the Crimea. Nightingale used the meeting to push for a Royal Commission to examine the high death rates. What had really happened out there?
As well as contributing to the commission, Nightingale continued with her own research into the hospital data. This work accelerated after she met statistician William Farr at a dinner party that autumn. The two had very different backgrounds: Nightingale came from the upper class, with a name reflecting her childhood in Tuscany, while Farr had been raised in poverty in rural Shropshire, eventually studying medicine before moving into medical statistics.[33]
When it came to population data in the 1850s, Farr was the man to speak to. Alongside his work on outbreaks like smallpox, he had set up the first national system to collate data on things like births and deaths. However, he’d noticed that these raw statistics could be misleading. The total number of deaths in a particular area would depend on how many inhabitants there were, as well as factors like age: a town with an elderly population would generally have more deaths each year than a town full of young people. To solve this problem, Farr came up with a new measurement. Rather than study total deaths, he looked at the rate of death per thousand people, accounting for things like age. It meant he could compare different populations in a fair way. ‘The death-rate is a fact; anything beyond this is an inference,’ as Farr put it.[34]
Working with Farr, Nightingale applied these new methods to data from the Crimea. She showed that death rates in army hospitals were much higher than wards in Britain. She also measured the decline in disease after the health commissioners arrived in 1855. As well as producing tables of data, she took full advantage of a new trend in Victorian science: data visualisation. Economists, geographers and engineers had increasingly used graphs and figures to make their work more accessible. Nightingale adapted these techniques, converting her key results into bar graphs and pie chart-like figures. Like Snow’s maps, the graphics focused on the most important patterns, free of distractions. The visuals were clear and memorable, helping her message to spread.
In 1858, she published her analysis of health in the British Army as an 860-page book. Copies were shipped to leaders ranging from Queen Victoria and the Prime Minister to newspaper editors and European heads of state. Whether looking at hospitals or communities, Nightingale believed that nature followed predictable laws when it came to disease. She said those disastrous early months in Crimea happened because people ignored these laws. ‘Nature is the same everywhere, and never permits her laws to be disregarded with impunity.’ She was also adamant about what had caused the problems. ‘The three things which all but destroyed the army in Crimea were ignorance, incapacity, and useless rules.’[35]
Nightingale’s advocacy sometimes made Farr nervous. He warned her against focusing too heavily on messages rather than data. ‘We do not want impressions,’ he said. ‘We want facts.’[36] Whereas Nightingale wanted to suggest explanations for the cause of the deaths, Farr believed the job of a statistician was simply to report what had happened, rather than speculating about why. ‘You complain that your report would be dry,’ he once told her. ‘The drier the better. Statistics should be the driest of all reading.’
Nightingale used her writing to campaign for change, but she’d never wanted to be just a writer. When she first decided to train as a nurse in the 1840s, it came as a surprise to her wealthy, well-connected family, who’d expected her to pursue the more traditional role of wife and mother. A friend suggested that she could still pursue a literary career alongside this role. Nightingale was not interested. ‘You ask me why I do not write something,’ she replied. ‘I think one’s feelings waste themselves in words; they ought all to be distilled into actions and into actions which bring results.’[37]
When it comes to improving health, actions need to be grounded in good evidence. Today, we routinely use data analysis to show how much health varies, why that might be, and what needs to be done about it. Much of this evidence-based approach can be traced to statisticians like Farr and Nightingale. As she saw it, people generally had little grasp of what controlled infections and what didn’t. In some cases, hospitals may well have increased people’s risk of disease. ‘These institutions, created for the relief of human distress, positively do not know whether they relieve it or not,’ as she put it.[38]
Nightingale’s research was highly respected by her scientific contemporaries, including statistician Karl Pearson. In the
