Doll was as shocked as anyone by the damning evidence against smoking: ‘I myself did not expect to find smoking was a major problem. If I’d had to bet money at that time, I would have put it on something to do with the roads and motorcars’. Doll and Hill did not start their research in order to achieve a specific result, but instead they were merely curious and concerned about getting to the truth. More generally, well-designed scientific studies and trials are not engineered to achieve an expected outcome, but rather they should be transparent and fair, and those conducting the research should be open to whatever results emerge.
The British Doctors Survey and similar studies were attacked by the tobacco industry, but Doll, Hill and their colleagues fought back and demonstrated that rigorous scientific research can establish the truth with such a level of authority that even the most powerful organizations cannot deny the facts for long. The link between smoking and lung cancer was proved beyond all reasonable doubt because of evidence emerging from several independent sources, each one confirming the results of the other. It is worth reiterating that progress in medicine requires independent replication — i.e. similar studies by more than one research group showing similar findings. Any conclusion that emerges from such a body of evidence is likely to be robust.
Hill and Doll’s research ultimately led to a raft of measures designed to persuade us not to smoke, which in turn has resulted in a 50 per cent decrease in smoking in many parts of the developed world. Unfortunately, smoking still remains the single biggest cause of preventable deaths worldwide, because significant new markets are opening up in the developing world. Also, for many smokers the addiction is so great that they ignore or deny the scientific evidence. When Hill and Doll first published their research in the
While we were writing this book, the
First, every breakthrough on the list illustrated the power of science to improve and save lives. For example, the list included oral rehydration, which helps recovery from diarrhoea and which has saved 50 million children’s lives in the last twenty-five years. The list also included antibiotics, germ theory and immunology, which together have helped to cure a whole range of diseases, thereby saving hundreds of millions of lives. Vaccines, of course, were on the list, because they have prevented many diseases from even occurring, thereby saving hundreds of millions more lives. And awareness of the risks of smoking has probably saved a similar number of lives.
The second point is that the concept of evidence-based medicine was also recognized among the top fifteen breakthroughs, because it too is a truly great medical achievement. As mentioned earlier, evidence-based medicine is simply about deciding best medical practice based on the best available evidence. It lacks the glamour and glitz of some of the other shortlisted breakthroughs, but it is arguably the greatest one because it underpins so many of the others. For example, the knowledge that vaccines and antibiotics are safe and protect against disease is only possible thanks to evidence gathered through clinical trials and other scientific investigations. Without evidence-based medicine, we risk falling into the trap of considering useless treatments as helpful, or helpful treatments as useless. Without evidence-based medicine we are likely to ignore the best treatments and instead rely on treatments that are mediocre, or poor, or useless, or even dangerous, thereby increasing the suffering of patients.