Historical figure · Pearson Edexcel International GCSE revision on Incandio

Richard Doll

The Man Who Proved Smoking Kills · Epidemiologist · 1912–2005

The epidemiologist who proved that smoking causes lung cancer, having expected to find the cause was something else entirely.

Defend these ideas against Doll

Incandio is a free revision platform for the Pearson Edexcel International GCSE, and on it a topic counts as mastered only once you have learned it, proved it in questions, taught it back and defended it against the person with the strongest claim on it. Richard Doll is that person for one topic on the course:

• Alveoli, Exercise and Smoking — Biology

Who was Doll?

Richard Doll was born in Hampton in 1912, studied medicine at St Thomas's, and served as an army medical officer in the Second World War. In 1947, with the statistician Austin Bradford Hill, he was asked to investigate why deaths from lung cancer had risen roughly fifteen-fold in twenty-five years. Doll's own expectation was that the cause would be tar from newly surfaced roads or fumes from motor cars. Interviewing hospital patients in London, the pattern that emerged instead was tobacco: patients with lung cancer were overwhelmingly more likely to be heavy smokers than patients admitted for other reasons. Doll gave up his own cigarettes two-thirds of the way through the study. Because a case-control result could always be attacked as biased, he and Hill then did something far more powerful: in 1951 they wrote to every doctor on the British medical register, asking about their smoking, and followed the 34,000 who replied for the rest of their lives — the British Doctors Study, which ran for fifty years. The results arrived in stages: by 1954 a clear excess of lung-cancer deaths in smokers; by 1956 a dose relationship; and by the fifty-year report in 2004 the full account — about half of all persistent smokers are killed by the habit, smokers lose about ten years of life, and those who stop, even in middle age, regain most of what they would have lost. He also demonstrated the dangers of asbestos and of radiation in pregnancy, and the protective effect of aspirin. He died in 2005, aged 92, a non-smoker for over half a century.

Major achievements

• Proved that smoking causes lung cancer, with Austin Bradford Hill (1950 case-control study; 1954 first cohort results)
• Designed and ran the British Doctors Study — 34,000 doctors followed for fifty years
• Established the dose–response relationship: the more smoked, the greater the risk
• Showed that stopping smoking recovers most of the lost life expectancy, even in middle age
• Demonstrated the cancer risk of asbestos, and of X-raying pregnant women

Life in brief

• 1912 — Born in Hampton: Son of a doctor.
• 1947 — Asked to explain the lung-cancer rise: With Bradford Hill, for the MRC. He expected road tar.
• 1950 — The case-control study published: Lung-cancer patients were overwhelmingly heavy smokers.
• 1951 — The British Doctors Study begins: 34,000 doctors answer a letter about their smoking.
• 1954 — First cohort results: A clear excess of lung-cancer deaths among smokers.
• 1956 — Dose–response established: The more smoked, the greater the risk.
• 2004 — The fifty-year report: Half of persistent smokers killed by it; ten years of life lost; quitting recovers most.
• 2005 — Dies aged 92: A non-smoker for over fifty years.

Explore the life of Doll — five chapters

1. Why Had Lung Cancer Increased Fifteenfold? — 1947, and a question nobody could answer
2. Interviewing Patients in London Hospitals — The case-control study, 1948 to 1950
3. The Best Statistician in the World Says You Are Wrong — Fisher's objection, and why it had to be answered
4. Fifty Years — The British Doctors Study, 1951 to 2001
5. The Payments Disclosed After His Death — A reputation, and a complication

Read the five-chapter life of Richard Doll →

Where Doll appears in your course

Richard Doll has a genuine claim on 1 lesson of the Pearson Edexcel International GCSE science course built into Incandio:

• Alveoli, Exercise and Smoking — Biology: You cannot assign half a population to smoke for thirty years, so the harm on this page had to be proved another way. Doll expected the rise in lung cancer to be caused by tarred roads; his data said tobacco, and he gave up his own cigarettes before publishing. He and Bradford Hill then followed 34,000 doctors for fifty years, and answered every objection — including the serious argument that smokers might simply be different people — with evidence rather than indignation.

Begin

• Start a conversation with Doll — a dramatised, historically grounded AI portrayal
• Read the Historical Brief
• Explore the life of Doll — five chapters
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