Category Archives: Public Health

In my mind, it is a subset of Global Health, often more locally focused.

Public Health is not a specialisation of medicine

Medicine saves lives one at a time. Public Health saves lives by the millions.

In many countries, the guilds of the medical fraternity provide for specialist membership. Attached to membership is prestige, promotion, and increased earning potential. In almost all cases, membership or fellowship of one of these guilds, typically titled “Colleges”, indicates increased expertise in the management of classes of disease in individual patients.

If you have diabetes, atrial fibrillation, Parkinson’s disease, major depression, etc., or you need more or less specialised surgery, you may well want to consult a member of one of these guilds of medicine.


Vaccination programs are critical to Public Health, but they do not require a medical specialisation in Public Health. [Image source:]

The focus of Public Health is the protection and improvement of the health of populations. The breadth of public health practice is enormous with individuals working in disease specific areas (e.g., HIV, TB, or mental health); settings (e.g., schools, workplaces, markets); social policy areas of the social determinants of health; health systems; health financing and market regulation; urban design; and health data analytics, to name just a few. Although there are commonalities between them, Public Health may be contrasted with Community Medicine and Social Medicine by the fact that Public Health practitioners do not spend their time treating individual patients, although they may guide services for the better and more efficient treatment of populations of patients.

The most significant distinction is that Public Health draws its expertise from a wide range of disciplines: behavioural sciences, nursing, management, geography, history, politics, anthropology, environmental sciences, urban planning, sociology, pharmacy, economics, biostatistics, microbiology, ecology, mathematics, parasitology, computer science, entomology, engineering, veterinary science, … and medicine. Some of the best public health people I have ever worked with have come from history and geography. It is not that history and geography are peculiarly crucial to Public Health. It is that good Public Health requires interdisciplinary teams that can bring new perspectives to problems. It is relatively unusual to find historians and geographers in Public Health, so they bring novel solutions that are quite different from those one might otherwise see.

Postgraduate Public Health training, such as a Masters of Public Health (MPH), is a useful way of providing the diverse disciplines involved in Public Health a common language with which to share problems, ideas, and solutions. There is no one best discipline for Public Health, and there is no reason that one has to study Public Health formally to make a valuable contribution to Public Health practice. I speak here as a person who has no formal qualification in Public Health but one who has been a Professor of Public Health, has lead Public Health teams, and has advised governments, UN agencies and international NGOs on Public Health.

I return to my titular point. Public Health benefits enormously from the input of people with a diverse range of qualifications. What then is the purpose of a medical specialisation in Public Health, if Public Health is not a branch of medicine?

The answer is historical and political. The historical answer is that Public Health is traditionally located within the Ministry of Health (MOH). There is a logic to this. So much of the practice of Public Health is about the coordination, regulation and efficient delivery of health services that it must be coordinated with MOH activities. The obvious down-side of this historical location of Public Health is that, as it has become increasingly evident that population health problems require whole of government approaches, any attempts to transcend the departmental pillars of government are regarded by other Ministries as a MOH power-grab.

Politically, power within MOH is typically vested in people with membership in one of the specialist guilds of medicine. The only way for Public Health to have status in MOH (and let’s face it, Public Health has never been as sexy as clinical medicine) is for it to be lead by people with a medical qualification and membership of a specialist guild. Thus, specialist guilds of Public Health medicine were born.

This historical and political strategy protected the status of Public Health within MOH. It provided a career pathway for medically qualified personnel interested in pursuing a career in Public Health. Unfortunately, it also limited the capacity of Public Health practice to deliver the best population health outcomes.

Governments need to improve the way they approach the protection, promotion and improvement of the health of their populations. A good start is to recognise that medicine is a part of the practice of Public Health (just as history, geography, etc. are), but Public Health is much bigger than a specialisation of medicine.

Donald Trump’s BMI: getting the measure of the man.

I find myself fascinated by a pointless lie because it is inescapably tragic. All it can do is diminish the person in the eyes of others. And this brings us to Donald Trump’s height. In January 2018, the Physician to the President, Ronny L. Jackson MD asserted that Donald Trump was 6’3″ tall (1.90m). This is so unlikely to be true, that it stretches credulity. There is no reason for Jackson to lie spontaneously about a patient’s height, and it seems probable that he was encouraged to add a few inches by the President himself.

When asked to self report height both men and women in the US tend to overstate it.  Burke and Carman have suggested that overstating height is motivated by social desirability — you can never be too tall. There is ample evidence of Donald Trump’s (misplaced) search for the socially desirable with respect to his hair, his tan, his ethnicity, his intelligence and now his height.

In 2018 we learnt that Donald Trump was officially not quite Obese (body mass index (BMI) <30), and in 2019 he had nudged over the line into the obese range (BMI 30). Overstating height creates a problem in the calculation of BMI — which is mass (in kilograms) divided by height (in meters squared). Given that Donald Trump is likely shorter than 1.9m (6’3″), and probably closer to 1.854m (6’1″) this will have implications for whether he was really obese in 2018 (not just overweight as stated by his Physician) and just how obese he probably is (Figure 1).

Figure 1: Donald Trump’s BMI in 2018 and 2019 given different assumptions about his height [R-code here].

In 2018 Donald trump was just below the obese category if and only if he was really 6’3″ (1.9m) tall.  At any height less than that he was obese in 2018 and he is obese today.  His most likely true height given comparisons with others (cf, Barack Obama) is 6’1″, and this puts him comfortably in the obese range.

Misrepresenting one’s height does not create a problem if the lie is reserved for others — except perhaps in a political sense. Problems arise if one deludes oneself. Telling others that you are taller and healthier than you really are is one thing; if you lie to yourself you cannot properly manage your health.




Play with Big Tobacco and you will be tarred

Philip Morris International (PMI), profits by selling the world’s leading cause of preventable death — tobacco. The Foundation for a Smoke-Free World (FSFW) recently handed PMI a public relations coup by accepting a $1 Billion donation. Who now could credibly work with FSFW?

PMI is the world’s largest, international tobacco company.  It is quite explicitly not interested in a tobacco-free world and it works hard and secretly to subvert tobacco control. Its raison d’être is the sale of tobacco products, and the “smoke-free world” cover provided by FSFW looks like a Big Tobacco tactic in a long line of them.

There is little doubt that FSFW as an organisation has placed itself in moral jeopardy by accepting PMI’s money: “Moral jeopardy occurs when a person or an organisation attempts to do good using resources from a source that involves harm.” And here is the rub.  One of FSFW’s stated goals is to support global research through the support of “Centers of Excellence”.  Any research group, however, that accepts FSFW money is exposing itself to moral jeopardy. And like other health and medical research outputs from conflicted industry sources, the results cannot be trusted — no matter how genuine the researchers are in their belief of independence.

PMI’s money laundering scheme for researchers may provide a scent of freshness, but the tobacco tar will stick.

Does global health need a ‘red team’?

Looking at population health, time-series data it is easy to imagine that everything is getting better and better. What is more, as your eye tracks the line into some imaginary future, it is easy to believe that things will continue to get better and better.  It is a soothing balm to the more insidious thought, that doom awaits us around every corner.  In the world of stock pickers and equities experts, the balm is the Ying of the bull to the Yang of the bear. Hope versus despair.

The late Hans Rosling has done more to ground people in that hopeful view of the future than any other person.  The gapminder website, his creation, provides clear, firm evidence of global improvements in health and well-being across a wide range of outcomes.  As you follow the motion picture trends, countries improve. Some occasionally collapse, horribly. Then they recover. And on average, all improve.  Poverty, life expectancy, education, the infant mortality rate — it does not matter what you focus on, the world has been getting better and better

Figure 1 is a quick snapshot of this improvement in life expectancy from 1915 and 2015. In both years, higher national wealth was associated with better life expectancy.  In 1915, a country with a GDP/capita (adjusted for inflation and price) of $1,000 had a life expectancy of 30 years. In 2015 a country with a GDP/capita (adjusted for inflation and price) of $1,000 had a life expectancy of 60 years.


Figure 1. The left and right panels show the countries’ life expectancy in relationship to the GDP/capita (adjusted for inflation and price) 100 years apart. In 1915 a country with a GDP/capita of $1000 had a life expectancy around 30 years. In 2015 it was around 60 years — a difference of about 30 years. Source: Gapminder

In contrast, in the middle of the 18th Century, life expectancy was similar across all countries, without regard to national wealth. Little had changed by the middle of the 19th Century. Sixty years later (1915), there was a strong association between national wealth and life expectancy; and over the next 100 years, things became much better for everyone.

Will this continue?

Let’s hope that it will.  There are however significant threats visible on the horizon — and I would argue that Global Health needs a strong Red Team to make plain that dreadful prospect, often and forcefully. And as the Red Team argues their side we should hope fervently that they are utterly and comprehensively wrong! We should nonetheless listen to the arguments and not glaze over or dismiss them as we would Cassandra.

Red Teams arose in the US military and intelligence communities. They were there to argue against self-satisfied complacency. If the majority view was purple, they argued orange, if Winter, then Summer. Their purpose was to find the weaknesses in the status quo. One of the most extraordinary examples of the power of a contrarian view was the Millenium Challenge 2002, in which Paul van Riper showed that a demonstrably weaker force (the Red Team) could be devastatingly effective against the powerful (Blue Team) when they were prepared to play outside the constrained paradigm of accepted norms.

In Global Health the situation is, of course, entirely different — we do not battle each other, but we do struggle with (and against)  nature and the environment.  What is not different between Intelligence agencies and Global Health agencies is that views become entrenched. The Philosopher of Science, Thomas Kuhn, described the entrenchment of scientific ideas in terms of normal science: “the regular work of scientists theorizing, observing, and experimenting within a settled paradigm or explanatory framework”. These “settled paradigms” can permit significant new developments, but they brook no serious opposition (only tinkering at the margins). They are the VHS manufacturer to the plucky Betamax.

“Beta what?”, I hear you ask, and the point is made.

Global Health has large, powerful groups that are in danger of playing a form of technocratic hegemony — Global Health, normal science.  It’s incremental, unabrasive, and potentially wrong or ineffectual. Some of the possible threats to global health are well known, and if we focus only on those related to climate change and population growth the following is a reasonable starting list:

The global expansion of humans over the past 10,000 years was made possible by the growth of agriculture, which in turn was made possible by a stabilisation in the climate about … 10,000 years ago.  Our current success is again a product of agricultural developments. Paul Ehrlich, in his 1968 book The Population Bomb wrote a Malthusian tale of global starvation.  His prediction failed to take account of Norman Borlaug’s green revolution, and the development of semidwarf wheat, which saw grain yields triple in the 1960s and 1970s. The predicted cycle of devastating starvation was averted.

Success in the past, unfortunately, does not tell us anything about the future. Timely science then does not predict timely science now. Although Borlaug’s work saw Ehrlich’s predicted threats displaced in time, towards the end of his Nobel Prize acceptance speech, Borlaug said:

Malthus signaled the danger a century and a half ago. But he emphasized principally the danger that population would increase faster than food supplies. In his time he could not foresee the tremendous increase in man’s food production potential. Nor could he have foreseen the disturbing and destructive physical and mental consequences of the grotesque concentration of human beings into the poisoned and clangorous environment of pathologically hypertrophied megalopoles. Can human beings endure the strain? Abnormal stresses and strains tend to accentuate man’s animal instincts and provoke irrational and socially disruptive behavior among the less stable individuals in the maddening crowd.

We must recognize the fact that adequate food is only the first requisite for life. For a decent and humane life we must also provide an opportunity for good education, remunerative employment, comfortable housing, good clothing, and effective and compassionate medical care. Unless we can do this, man may degenerate sooner from environmental diseases than from hunger.

So far, the international, multilateral approach to a possibly gloomy future is to seek hope — it does, after all, spring eternal.  We will reduce greenhouse gas emissions, tackle global poverty through economic growth, and increase food production. We will not need to tackle population growth, nor will we have to make do with less. We write about planetary health, but we do not develop strategies for a planet that is less human-friendly tomorrow than it is today.

I hope that global health and well-being will improve well into the future, well past my life and I hope well past that of my children, (and their children, …). In case it does not, I would like to think that there is a Global Health Red Team that does not just echo gloomy news in the halls of power, but argues for and develops strategies suitable for the world in which we are all worse off.  What should our goal be in that worse off world?  Is it a global goal, an equitable goal of mutual pain, or is it a “My Country First”, Shakespearean tragedy of the commons?

There is an ironic twist to the use of Red Teams in the US military that may have some bearing on their use in Global Health.  In the Millenium Challenge 2002 when the Red Team devastated the Blue Team in the first few days of a fortnight-long exercise, the judges reset the clock. They hamstrung the Red Team, and then let everything play out in a way that would ensure that normal (military) science came out unscathed.

Global Health needs to be intellectually braver.