Conflicts of interest

The possibility or likelihood of conflict of interest is present in virtually all professions and occupations. We expect a researcher, a physician, or a legislator to perform her work according to the highest values and norms of their work (searching for objective knowledge, providing the best care possible for the patient, drafting and supporting legislation in order to enhance the public good). But there is always the possibility that the individual may have private financial interests that distort or bias the work she does, and there may be large companies that have a financial interest in one set of actions rather than another.

Marc Rodwin's Conflicts of Interest and the Future of Medicine: The United States, France, and Japan is a rigorous and fair treatment of this issue with respect to conflicts of interest in the field of medicine. Rodwin has published extensively on this topic, and the current book is an important exploration of how professional ethics, individual interest, and business and professional institutions intersect to influence practitioner behavior in this field. The institutional actors in this story include the pharmaceutical companies and medical device manufacturers, insurers, hospitals and physician partnerships, and legislators and regulators. Rodwin shows in detail how differences in insurance policies, physician reimbursement policies, and gifts and benefits from health-related businesses to physicians contribute to an institutional environment where the physician's choices are all too easily influenced by considerations other than the best health outcomes of the patient. Rodwin finds that the institutional setting for health economics is different in the US, France, and Japan, and that these differences lead to differences in physician behavior.

Here is Rodwin's clear statement of the material situation that creates the possibility or likelihood of conflicts of interest in medicine.

Physicians earn their living through their medical work and so may practice in ways that enhance their income rather than the interests of patients. Moreover, when physicians prescribe drugs, devices, and treatments and choose who supplies these or refer patients to other providers, they affect the fortunes of third parties. As a result, providers, suppliers, and insurers try to influence physicians' clinical decisions for their own benefit. Thus, at the core of doctoring lies tension between self-interest and faithful service to patients and the public. The prevailing powerful medical ethos does influence physicians. Still, there is conflict between professional ethics and financial incentives. (kl 251)

Jerome Kassirer is a former editor-in-chief of the New England Journal of Medicine, and an expert observer of the field, and he provided a foreword to the book. Kassirer describes the current situation in the medical economy in these terms, drawing on his own synthesis of recent research and journalism:

Professionalism had been steadily eroded by complex financial ties between practicing physicians and academic physicians on the one hand and the pharmaceutical, medical device, and biotechnology industries on the other. These financial ties were deep and wide: they threatened to bias the clinical research on which physicians relied to care for the sick, and they permeated nearly every aspect of medical care. Physicians were accepting gifts, taking free trips, serving on companies' speakers' bureaus, signing their names to articles written for them by industry-paid ghostwriters, and engaging in research that endangered patient care. (kl 73)

The fundamental problem posed by Rodwin's book is this set of questions:

In what context can physicians be trusted to act in their patients' interests? How can medical practice be organized to minimize physicians' conflicts of interest? How can society promote what is best in medical professionalism? What roles should physicians and organized medicine play in the medical economy? What roles should insurers, the state, and markets play in medical care? (kl 267)

The book sheds light on dozens of institutional arrangements that create the likelihood of conflicted choices, or that reduce that likelihood. One of those arrangements is the question for a non-profit hospital of whether the physicians are employed with a fixed salary or work on a fee-for-service basis. The latter system gives the physician a very different set of financial interests, including the possibility of making clinical choices that increase revenues to the physician or his or her group practice.

Consider physicians employed as public servants in public hospitals. Typically, they receive a fixed salary set by rank, enjoy tenure, and have clinical discretion. As a result, they lack financial incentives that bias their choices and have clinical freedom. Such arrangements preclude employment conflicts of interest. But relax some of these conditions and employers can compromise medical practice.... Furthermore, emplloyers can manage physicians to promote the organization's goals. As a result, employed physicians might practice in ways that promote their employer's over their patients' interests. (kl 445)

And the disadvantages for the patient of the self-employed physician are also important:

Payment can encourage physicians to supply more, less, or different kinds of services, or to refer to particular providers. Each form of payment has some bias, but some compromise clinical decisions more than others do. (kl 445) 

Plainly, the circumstances and economic institutions described here are relevant to many other occupations as well. Scientists, policymakers, regulators, professors, and accountants all face similar circumstances -- though the financial stakes in medicine are particularly high. (Here is an earlier post on corporate efforts to influence scientific research; link.)

This field of research makes an important contribution to a particular challenging topic in contemporary healthcare. But Rodwin's study also provides an important contribution to the new institutionalism, since it serves as a micro-level case study of the differences in behavior created by differences in institutional rules and practices.

Each country's laws, insurance, and medical institutions shape medical practice; and within each country, different forms of practice affect clinical choices. (kl 218)

This feature of the book allows it to contribute to the kinds of arguments on the causal and historical importance of specific configurations of institutions offered by Kathleen Thelen (link) and Frank Dobbin (link).

Patient safety

An issue which is of concern to anyone who receives treatment in a hospital is the topic of patient safety. How likely is it that there will be a serious mistake in treatment -- wrong-site surgery, incorrect medication or radiation dose, exposure to a hospital-acquired infection? The current evidence is alarming. (Martin Makary et al estimate that over 250,000 deaths per year result from medical mistakes -- making medical error now the third leading cause of mortality in the United States (link).) And when these events occur, where should we look for assigning responsibility -- at the individual providers, at the systems that have been implemented for patient care, at the regulatory agencies responsible for overseeing patient safety?

Medical accidents commonly demonstrate a complex interaction of factors, from the individual provider to the technologies in use to failures of regulation and oversight. We can look at a hospital as a place where caring professionals do their best to improve the health of their patients while scrupulously avoiding errors. Or we can look at it as an intricate system involving the recording and dissemination of information about patients; the administration of procedures to patients (surgery, medication, radiation therapy). In this sense a hospital is similar to a factory with multiple intersecting locations of activity. Finally, we can look at it as an organization -- a system of division of labor, cooperation, and supervision by large numbers of staff whose joint efforts lead to health and accidents alike. Obviously each of these perspectives is partially correct. Doctors, nurses, and technicians are carefully and extensively trained to diagnose and treat their patients. The technology of the hospital -- the digital patient record system, the devices that administer drugs, the surgical robots -- can be designed better or worse from a safety point of view. And the social organization of the hospital can be effective and safe, or it can be dysfunctional and unsafe. So all three aspects are relevant both to safe operations and the possibility of chronic lack of safety.

So how should we analyze the phenomenon of patient safety? What factors can be identified that distinguish high safety hospitals from low safety? What lessons can be learned from the study of accidents and mistakes that cumulatively lead to a hospitals patient safety record?

The view that primarily emphasizes expertise and training of individual practitioners is very common in the healthcare industry, and yet this approach is not particularly useful as a basis for improving the safety of healthcare systems. Skill and expertise are necessary conditions for effective medical treatment; but the other two zones of accident space are probably more important for reducing accidents -- the design of treatment systems and the organizational features that coordinate the activities of the various individuals within the system.

Dr. James Bagian is a strong advocate for the perspective of treating healthcare institutions as systems. Bagian considers both technical systems characteristics of processes and the organizational forms through which these processes are carried out and monitored. And he is very skilled at teasing out some of the ways in which features of both system and organization lead to avoidable accidents and failures. I recall his description of a safety walkthrough he had done in a major hospital. He said that during the tour he noticed a number of nurses' stations which were covered with yellow sticky notes. He observed that this is both a symptom and a cause of an accident-prone organization. It means that individual caregivers were obligated to remind themselves of tasks and exceptions that needed to be observed. Far better was to have a set of systems and protocols that made sticky notes unnecessary. Here is the abstract from a short summary article by Bagian on the current state of patient safety:

Abstract The traditional approach to patient safety in health care has ranged from reticence to outward denial of serious flaws. This undermines the otherwise remarkable advances in technology and information that have characterized the specialty of medical practice. In addition, lessons learned in industries outside health care, such as in aviation, provide opportunities for improvements that successfully reduce mishaps and errors while maintaining a standard of excellence. This is precisely the call in medicine prompted by the 1999 Institute of Medicine report “To Err Is Human: Building a Safer Health System.” However, to effect these changes, key components of a successful safety system must include: (1) communication, (2) a shift from a posture of reliance on human infallibility (hence “shame and blame”) to checklists that recognize the contribution of the system and account for human limitations, and (3) a cultivation of non-punitive open and/or de-identified/anonymous reporting of safety concerns, including close calls, in addition to adverse events.

(Here is the Institute of Medicine study to which Bagian refers; link.)

Nancy Leveson is an aeronautical and software engineer who has spent most of her career devoted to designing safe systems. Her book Engineering a Safer World: Systems Thinking Applied to Safety is a recent presentation of her theories of systems safety. She applies these approaches to problems of patient safety with several co-authors in "A Systems Approach to Analyzing and Preventing Hospital Adverse Events" (link). Here is the abstract and summary of findings for that article:

Objective: This study aimed to demonstrate the use of a systems theory-based accident analysis technique in health care applications as a more powerful alternative to the chain-of-event accident models currently underpinning root cause analysis methods.
Method: A new accident analysis technique, CAST [Causal Analysis based on Systems Theory], is described and illustrated on a set of adverse cardiovascular surgery events at a large medical center. The lessons that can be learned from the analysis are compared with those that can be derived from the typical root cause analysis techniques used today.
Results: The analysis of the 30 cardiovascular surgery adverse events using CAST revealed the reasons behind unsafe individual behavior, which were related to the design of the system involved and not negligence or incompetence on the part of individuals. With the use of the system-theoretic analysis results, recommendations can be generated to change the context in which decisions are made and thus improve decision making and reduce the risk of an accident.
Conclusions: The use of a systems-theoretic accident analysis technique can assist in identifying causal factors at all levels of the system without simply assigning blame to either the frontline clinicians or technicians involved. Identification of these causal factors in accidents will help health care systems learn from mistakes and design system-level changes to prevent them in the future.
Key Words: patient safety, systems theory, cardiac surgical procedures, adverse event causal analysis (J Patient Saf 2016;00: 00–00)

Crucial in this article is this research group's effort to identify causes "at all levels of the system without simply assigning blame to either the frontline clinicians or technicians involved". The key result is this: "The analysis of the 30 cardiovascular surgery adverse events using CAST revealed the reasons behind unsafe individual behavior, which were related to the design of the system involved and not negligence or incompetence on the part of individuals."

Bagian, Leveson, and others make a crucial point: in order to substantially increase the performance of hospitals and the healthcare system more generally when it comes to patient safety, it will be necessary to extend the focus of safety analysis from individual incidents and agents to the systems and organizations through which these accidents were possible. In other words, attention to systems and organizations is crucial if we are to significantly reduce the frequency of medical and hospital mistakes.

(The Makary et al estimate of 250,000 deaths caused by medical error has been questioned on methodological grounds. See Aaron Carroll's thoughtful rebuttal (NYT 8/15/16; link).)

Life quality across structural change

Periods of rapid structural change are particularly likely to lead to decline in the quality of life of some sections of the affected population. Change creates winners and losers; and it is common that the gains and losses are channeled into very distinct groups of people.  This is true during periods of large-scale migration, technology change, and structural change within an economy. Important components of life quality include health, nutrition, education, economic wellbeing, economic security, and security from violence and coercion. Each of these properties is affected by several important dimensions of social life:

• legal and political institutions
• institutions of economic production and distribution
• economic opportunities and income
• public provision of income supplements
• public provision of food subsidies
• public provision of health care resources
• household support provided by family and community

When a society's governmental and economic institutions are enmeshed in a period of rapid change, many of the components of life quality are likely to be affected -- positively or negatively. The basic institutions of a society determine the value of the private and public assets individuals and households control on the basis of which to support their pursuit of a decent life; this is what Amartya Sen refers to as "entitlement bundles". (Sen applies his entitlement theory to the study of famine in Poverty and Famines: An Essay on Entitlement and Deprivation; link.) And shifts in the composition of the entitlement bundle are likely to lead to abrupt worsening of the conditions of the least-well-off.

For example: It is likely that the austerity policies of the Spanish or Greek governments will have a negative effect on the health and nutritional status of the bottom half of those societies. Working people will have lower incomes and they will have reduced access to the social safety net; health status is likely to decline. As another example: Life expectancy in the former Soviet Union declined measurably following the collapse of the Soviet system (link). One part of that decline was the disappearance of the social security net created by state-owned industry -- the smashing of the "iron rice bowl".

This concern is particularly relevant in the context of the rural-urban transformation currently underway in China. Since 1980 China's rural sector has been subject to at least two major kinds of structural change. One has to do with the economic and political institutions that governed daily life for rural households, from communes to market institutions. And the other has to do with the rapid structural transformation of China's economy from agriculture to export-led manufacturing. The first set of changes led to a withdrawal of forms of "social insurance" that had been associated with the commune system, including healthcare and old-age care. The second has led to mass migration of younger workers from villages and towns to factories in cities. This migration leaves the remaining population in the countryside older, poorer, and less economically secure.

These observations have several important implications. Foremost among these is the crucial importance of maintaining effective systems for monitoring and measuring life quality across the society. It is important to have good measures of health status, nutritional status, educational status, and old age life quality across regions and sub-populations. So national governments need to create and fund the social research activities necessary to measure health and other quality of life properties across the population. (Here is a recent post on a spatial study of quality of life in China based on 1982 data; link.) Sen argues that it was the availability or lack of availability of information about famine conditions that explained the difference in outcomes between China during the Great Leap Forward and post-independence India; Poverty and Famines: An Essay on Entitlement and Deprivation.

Second, when it turns out that there are large numbers of "losers" in a large social process of change, it is important for the state and non-governmental actors to find institutions and resources that will help to improve their outcomes. "Winners" need to help to fund the amelioration of harms created by the processes that led to their gains. If NAFTA led to the increase of overall national income for Canada, Mexico, and the United States, but also led to the displacement of workers in a significant set of industries -- then it makes sense to tax part of those gains to compensate the losers. And in fact, the NAFTA agreements were premised on such compensation, though this has not occurred reliably (link). This means redistribution across sectors and regions; and it is justified by the fact that the overall gains created by the transformation would not have been possible without imposing these losses on the disadvantaged sector or region.

What might this kind of redistributive policy look like in the context of China's rural-to-urban transformation? It would seem that public moneys will be needed for several types of problems:

• Maintenance of income and quality of life and health for the elderly
• Investments that increase the productivity of labor and the level of employment in rural areas
• Investments that work to ameliorate the negative environmental effects of rapid change
• Investments in the institutions of public health -- clinics, hospitals, and medical personnel

It might be asked, "Why should developing nations concern themselves with this issue?" There are several answers. Basic justice and fairness entails that the wealth of a society should be distributed in ways that allow all segments of society to improve their quality of life and wellbeing. A society's wealth and income is a joint product of its entire population; so fairness dictates that everyone should benefit from improvements in productivity. But prudence lines up with this answer as well. A society that ignores the widening of the gaps between rich and poor, and does not concern itself about improving the wellbeing of the poor, is likely to suffer a rising level of social strife as well. It can either go the route of creating gated communities for the rich, or it can use its resources to create fair life outcomes and fair access to opportunity for all its people. Everyone is better off in the long run with the second choice.

In The Paradox Of Wealth And Poverty: Mapping The Ethical Dilemmas Of Global Development I argued that a developing nation should choose an economic development strategy that spreads the benefits of growth over a broader population, over a strategy with a higher growth rate but with substantially greater inequality. I still think this is the right answer to the question. And this approach has the best likelihood of improving the quality of life of the poorest segment of society. The graphs below make the case based on three stylized strategies:

1. NL neo-liberal growth: choose those policies and institutional reforms that lead to the most rapid growth: unfettered markets, profit-maximizing firms, minimal redistribution of in­come and wealth 
2. PF poverty-first growth: choose those policies and institutional reforms that lead to economic growth favorable to the most rapid growth in the incomes flowing to the poorest 2 quintiles 
3. WF immediate welfare improvement: direct as much social wealth as possible into programs that immediately improve the welfare of the poor (education, health, food subsidies, housing subsidies)  

 

The neo-liberal strategy consistently maximizes GDP; but the poverty-first strategy, which is more redistributive from the start, leads to consistently better improvement for the income for the bottom 40% of the economy.  It embodies the idea that Hollis Chenery advocated forty years ago in Redistribution with Growth: Policies to Improve Income Distribution in Developing Countries in the Context of Economic Growth.

Running on empty

We've been focusing on the 1 percent and the 99 percent for the past year, thanks to the Occupy movement. But here's another way of slicing American society -- right down the middle. How is the 50 percent doing these days?

The answer seems to be, not very well. And the conservative assault on the social safety net pretty much guarantees that this part of American society will do even worse in the coming years. Poverty is concentrated in this half of America, both adult and child; the percentage of uninsured people is high; and the median income has dropped significantly since 2000. The inequalities that have worsened in the US since 1980 have hurt the bottom half significantly.

Here is a summary from USAToday in 2011 (link):

Median household income fell 2.3% to $49,445 last year and has dropped 7% since 2000 after adjusting for inflation, the Census Bureau said Tuesday. Income was the lowest since 1996.

Poverty rose, too. The share of people living in poverty hit 15.1%, the highest level since 1993, and 2.6 million more people moved into poverty, the most since Census began keeping track in 1959.

The poverty statistic is stunning: it implies that 30 percent of the bottom 50 percent are officially living in poverty -- almost one-third.

So how do the bottom half of Americans do when it comes to health insurance? The Kaiser Family Foundation provides a major data source on rates of uninsured adults by income group (link). Here is a data snapshot for uninsured non-elderly Americans by income:

This shows that 58% of non-elderly Americans with income below 250% of the Federal poverty line are uninsured, while 12% of non-elderly Americans between 250% and 400% of FPL are uninsured. Only 5% of non-elderly Americans with income in excess of 400% of the Federal poverty line are uninsured.

What does this distribution of uninsured status across income imply for the bottom half of Americans? This requires some calculation.  Here are the Federal poverty lines for 2011 (link):


A household of 4 persons has a Federal poverty line of $22,350 on this standard, so 250% of this is $55,875 -- a bit above the median household income for 2011.  So lack of health insurance is heavily concentrated in the bottom 50 percent.

Home foreclosure is another reality in middle income America. Foreclosure has been a reality across full range of the income spectrum since 2008.  But it appears to be more devastating in the bottom half of the income distribution.  (This is evident in Detroit and Southeast Michigan.)

What is our society doing about these basic realities?  Not very much.  And, of course, a major candidate for President is on record: "I'm not concerned about the very poor" (link).  One would hope that the bottom 50 percent think very carefully about which political platform best serves their real interests, including maintenance of a social safety net, aggressive and effective efforts to stimulate job growth, tax reform that requires the affluent to pay their fair share, and preservation of the broadened health insurance coverage promised by the 2010 health care reform legislation.

(Here is a piece in the New York Times on median income; link.)

Health disparities in the US and China

Health disparities across a population are among the most profound indicators of social inequalities that we can find.  And the fact of significant disparities across groups is a devastating statement about the circumstances of justice under which a society functions.  These disparities translate into shorter lives and lower quality of life for whole groups of people, relative to other groups.

Both the United States and China appear to display significant health disparities across their populations. Here are a couple of studies that draw attention to these facts.

United States

Here is an important new study on the question of health disparities in the United States by public health researchers at Harvard and UCSF.  The study is "Eight Americas: Investigating Mortality Disparities across Races, Counties, and Race-Counties in the United States". And the answer the researchers provide to the question above is that the US possesses very significant health disparities across segments of its population. The study is worth reading in detail.

The authors analyze mortality statistics by county, and they break the data down by incorporating racial and demographic characteristics. The data groups fairly well around the eight Americas mentioned in the title:


Here is how they describe their findings:

The gap between the highest and lowest life expectancies for race-county combinations in the United States is over 35 y. We divided the race-county combinations of the US population into eight distinct groups, referred to as the “eight Americas,” to explore the causes of the disparities that can inform specific public health intervention policies and programs.

And here is their conclusion:

Disparities in mortality across the eight Americas, each consisting of millions or tens of millions of Americans, are enormous by all international standards. The observed disparities in life expectancy cannot be explained by race, income, or basic health-care access and utilization alone. Because policies aimed at reducing fundamental socioeconomic inequalities are currently practically absent in the US, health disparities will have to be at least partly addressed through public health strategies that reduce risk factors for chronic diseases and injuries.

For example, their data show that "the life expectancy gap between the 3.4 million high-risk urban black males and the 5.6 million Asian females was 20.7 y in 2001." This is an enormous difference in longevity for the two groups; and it is a difference that tags fundamental social structures that influence health and risk across these two populations.

Here is a time-series graph of the behavior of longevity for the eight Americas:
So what are the factors that appear to create these extreme differences in mortality across socioeconomic and racial groups in America? They consider health care access and utilization; homicide; accidents; and HIV as primary potential causes of variations in mortality for a group. Most important of all of these factors for the large populations appear to be the health disparities that derive from access and utilization.  And here they offer an important set of recommendations:

Opportunities and interventions to reduce health inequalities include (1) reducing socioeconomic inequalities, which are the distal causes of health inequalities, (2) increasing financial access to health care by decreasing the number of Americans without health plan coverage, (3) removing physical, behavioral, and cultural barriers to health care, (4) reducing disparities in the quality of care, (5) designing public health strategies and interventions to reduce health risks at the level of communities (e.g., changes in urban/neighborhood design to facilitate physical activity and reduce obesity), and (6) designing public health strategies to reduce health risks that target individuals or population subgroups that are not necessarily in the same community (e.g., tobacco taxation or pharmacological interventions for blood pressure and cholesterol).

These findings are squarely relevant to assessing the justice of our society. The country needs to recognize the severity of the "health/mortality equity" issue, and we need to make appropriate policy reforms so that these disparities begin to lessen.

China

Several research papers address these issues for the case of China.  One is a World Bank working paper by David Dollar called "Poverty, Inequality, and Social Disparities During China's Economic Reform" (link).  Dollar notes that China has dramatically reduced its poverty rate over the past 25 years, whereas its income inequality measures have increased sharply during the same period. (Albert Park and Sangui Wang review the poverty statistics for this period in China Economic Review; link.)  They conclude that these inequalities between rural and urban populations, and between well educated urban professionals and the urban working class, have also resulted in significant inequalities in health status and outcomes for the various sub-populations.

Shenglan Tank, Qingyue Meng, Lincoln Chen, Henk Bekedam, Tim Evans, and Margaret Whitehead review the current evidence available on health equity in China in "Tackling the challenges to health equity in China" (link).  "Although health gains have continued, concern for the equitable distribution of social benefits of economic progress has grown" (25).  Further:

Disparities in income and wealth between the urban and rural areas, between the eastern and western regions, and between households have widened substantially. In 1990, the richest province had a GDP per person more than seven times larger than the poorest province, but by 2002, the same ratio had grown to 13 times greater.41The Gini coefficient, a measure of income inequality,42increased for China as a whole from 0·31 in 1978–79 to 0·45 in 2004. The level of income inequality in China is now similar to that in the USA, roughly comparable to that in the most inequitable Asian countries—Philippines and Thailand—and approaching the notoriously inequitable levels in Brazil and Mexico. (29-30)

The authors quote Amartya Sen on health equity (Amartya Sen, Why health equity"; link):

Health equity cannot be concerned only with health in isolation. Rather it must come to grips with the larger issue of fairness and justice in social arrangements, including economic allocations, paying attention to the role of health in human life and freedom.  Health equity is most certainly not just about the distribution of health, not to mention the even narrower focus on the distribution of health care. Indeed, health equity has an enormously wide reach and relevance.

And inequalities in personal income in different provinces lead to highly different levels of ability to fund public amenities in these provinces, with large effects on public health in poor provinces:

Living conditions differ greatly between areas of different affluence. Safe drinking water is available to 96% of the population of large cities but to less than 30% in poor rural areas. Differences in access to effective sanitation are even larger, 90% of residents in large cities have adequate sanitation, compared with less than 10% in poor rural areas (figure 6).

Two graphs capture the big picture:

In figure 1 the data demonstrate a strong correlation between life expectancy and average income for China's provinces and municipalities, from just about 65 years for the poorest regions to 78 years in Shanghai region.  Figure 2 demonstrates major inequalities in child health between rural and urban locations.  The authors further report that infant mortality also varies dramatically across regions: "Rural infant mortality rates are nearly five times higher in the poorest rural counties than in the wealthiest countries -- 123 versus 26 per 1000 live births, respectively" (26). One important source of data on these issues that these researchers use is the Chinese National Health Service survey of 1998; link.

The most detailed analysis of health disparities in China I've been able to find is a paper published in 2010 by Feinian Chen, Yang Yang, and Guangya Liu, "Social Change and Socioeconomic Disparities in Health over the Life Course in China: A Cohort Analysis" (link).  They make use of the China Health and Nutrition Survey to allow for a longitudinal study of health in several segments of China's population. (Here is a description of the CHNS.) Their conclusion:

Using data from the China Health and Nutrition Survey, we find significant socioeconomic status (SES) differences in the mean level of health and that these SES differentials generally diverge over the life course. We also find strong cohort variations in SES disparities in the mean levels of health and health trajectories. (126)

It would appear that studies of health status in China disaggregated by population segments are not yet as fully developed as one would wish.  The CHNS appears to have limited data coverage (much more limited than the national census, for example), and none of the studies mentioned in these articles appear to disaggregate down to levels lower than the province.  But the summary findings of all three of these articles point in the same direction: it is probable that there are significant inter-regional and inter-sectoral inequalities in health outcomes for the sub-populations corresponding to these segments.