Mark Jackson has degrees in immunology and medicine, but while he was still in his first hospital job he decided that he "wanted to do a PhD before it was too late - and I never went back".
Now the director of the Centre for Medical History at the University of Exeter, he settled on a striking topic for his doctorate - the way medical evidence was used in cases of women accused of killing their children - a choice that helped to set the pattern for his career.
The results were eventually published in 1996 in his book New-Born Child Murder: Women, Illegitimacy and the Courts in Eighteenth-Century England.
"While the evidence itself was often equivocal," Jackson says, "I was interested in the way it was used to convict or acquit certain types of women, such as unmarried mothers, and in the changing role of medical evidence in the courts.
"Although things have obviously changed, the same issues - marital status, whether the woman concealed the pregnancy and birth - still tend to turn up in cases of infanticide."
As his comments suggest, Jackson is fascinated by the way medicine interacts with wider political and social factors and how the past can shed significant, if often indirect, light on the present. The books that followed his first have examined "imbecility", asthma and allergies.
In the case of Allergy: The History of a Modern Malady (2006), for example, he "saw allergy as both a biological and cultural phenomenon. The language of allergy is shaped by class, gender and racial expectations - and so helps us to see how our own assumptions are shaped in the same way."
His latest project considers stress as a response both to changing environments and political anxieties, requiring us to look at issues of social inequality alongside biology.
Although he has made a thorough transition from medic to medical historian, Jackson asserts that his medical training has been helpful in stimulating him to "ask different questions".
"I am part of both - often hostile - camps, and part of my agenda is to reconcile the two," he says. "Like many other medical historians, I have a strong desire to engage with medics as well as historians, and to contribute to current debates on health policy."
He continues: "Doctors are often deeply interested in the history of medicine and contribute articles to journals. So they share areas of interest with historians but use different methodologies."
There are, in Jackson's view, caricatures on both sides.
Historians sometimes claim that doctors write about the history of medicine simplistically, "in purely biographical and chronological terms, as a progressive story of victory over disease".
Medics can respond that historians are so concerned with context and relativism that they lose sight of the reality of sick and dying patients.
Bridging this gulf has been important to Jackson in his work as editor of the huge Oxford Handbook of the History of Medicine, published last month. While the work is notably wide-ranging in its geographical and historical coverage, and (he hopes) offers "a synoptic overview of the history of medicine for the first time in 20 years", he also notes that "most chapters are not just surveys but also critiques of how medical history has been done and how it could be done better".
Coverage of topics such as ageing, death, sexuality and public health reveals how "the medical and technical are integrally linked with the social and cultural".
There are inevitable questions about what to include in such a book and what kinds of value judgement are appropriate.
In discussing the medicine of China, sub-Saharan Africa and the Islamic world, Jackson says that the volume's contributors examine "both the independent traditions and how they fused with Western medicine. They tend not to pass judgement on what we might see as 'mystical' and 'mythical' traditions - I suspect some of our own ideas will look similar in 20 years."
Yet a chapter on different current systems of healthcare - private, insurance-based and funded through taxation - argues that we now have the tools for assessing the efficacy of past and present medical interventions, and that historians should not be afraid of using them.
Looking ahead, Jackson would like to see "further research on transnational developments, to make our understanding as global as we can". He believes it is equally important "to mobilise our history more imaginatively with contemporary issues".