The public health push, launched in 2016 by Chinese authorities in the northwestern region of Xinjiang, was pitched as a benevolent benefit: Residents would get free annual medical checkups. They’d be screened for diseases. And they’d get digital health records, in many cases for the first time.

But Physicals for All, as the program is known, is coming under fire from critics who say it has another purpose: government surveillance that violates the basic genetic privacy rights of millions of people in a region with many religious and ethnic minorities.

The public health program is a key arm of a larger government push to collect DNA and other biometric information in Xinjiang. The activist group Human Rights Watch recently slammed the initiative as “a gross violation of international human rights norms.’’ (China’s foreign ministry dismissed the accusations at a briefing last week.)

As part of Physicals for All, local health authorities are being ordered to collect residents’ DNA and assess their blood type, and then pass the data along to police “for profiling,’’ according to Human Rights Watch’s unofficial translation of a government document.

Nearly 19 million of Xinjiang’s residents underwent an exam in 2017 as part of Physicals for All, according to a November report from China’s state news agency. At the end of 2015, the region’s population was estimated at 23.6 million people. Close to half of the region’s residents are Uighurs, a mostly Muslim group. After violent attacks in Xinjiang that have been blamed on Islamic extremists, Chinese authorities have tightened control by increasing the police presence, ordering GPS trackers on cars, and banning long beards and veils.

An important caveat about the Physicals for All program: Details are murky about how and for what purposes it is being run. For example, it’s not clear what authorities are doing with the biometric data they’re collecting from Xinjiang residents.

Another point of uncertainty: the role of medical equipment made by Waltham-based Thermo Fisher Scientific, which became ensnared in the controversy after reports that it sold its DNA sequencers to Xinjiang police. Thermo Fisher spokesman Ron O’Brien wouldn’t confirm or deny these reports to STAT, but said that the company collaborates with research groups in China on work that has applications for forensics.

“We are confident that such programs can adequately protect personal privacy while appropriately balancing the public safety and national security needs of government,’’ O’Brien said.

So what should we make of the controversy around the Physicals for All program? STAT called experts who study the intersections of China, genetic data, and public health. Here are some of the questions they raised:

What does public health mean in China?

Chinese authorities often view public health through a different lens than the world’s leading public health professionals.

“From my experience in other parts of China, public health is government surveillance. Those two things can’t be separated,’’ said Katherine Mason, a medical anthropologist at Brown University who studies public health systems in China.

A top focus: addressing what Chinese authorities see as the national danger posed by people who are perceived to easily spread or catch infectious diseases, or to engage in unsanitary practices. That “means very often targeting minority groups, migrant workers, those folks who we would think of as vulnerable populations,’’ Mason said.

Consider, for example, the physical exams that have long been required of migrant workers who move from rural areas to Chinese cities to work in service industries like restaurants or massage parlors. To be allowed to work, these migrants must submit blood and fecal samples, undergo X-rays, and more. Mason cited her interviews with public health workers in China who described it as a way to keep tabs on the local migrant population and to understand what diseases might be circulating within it.

Are residents being coerced to get physicals?

Chinese authorities insist the Physicals for All program is voluntary.

But in Xinjiang, the program is seen “with a high level of suspicion’’ by many residents, who nonetheless “feel as if they have no choice but to participate,’’ said Darren Byler, a PhD candidate in anthropology at the University of Washington who studies Xinjiang, citing his interviews with Uighur residents.

Human Rights Watch reported interviewing an Uighur resident who said his neighborhood committee had demanded participation in the program, and that he felt he had to participate to avoid being labeled as politically disloyal.

Are residents told how their data will be used?

Concerns about coercion tie into another question: what Xinjiang residents who gave up their biometric data agreed to.

“How did they obtain the consent from local respondents, especially for those illiterate or those unable to speak or write in Chinese?’’ said Xi Chen, a health policy researcher at Yale University who studies China. “I vote for a thorough and transparent investigation on whether any illegal or unethical issues happened during this process.’’

Informed consent is a basic standard for medical visits and research. In a program like Physicals for All, experts said, participants should be told why their data are being collected; how their sample is — and is not — going to be used; how it’s going to be kept safe; and who is going to be given access.

The lack of clarity has helped generate a specific fear among Uighur residents: that the DNA data will be used to identify suspected criminals facing execution whose organs could be a match for recipients in need of a transplant, according to Byler, citing his interviews with Uighur residents.

Are residents benefiting from free physicals?

It’s not clear whether the biometric data being collected in Xinjiang are used for medical research. But there’s plenty of precedent for medical research in which researchers collect genetic information in exchange for a benefit, such as building community clinics or offering vaccinations.

In Xinjiang, it’s not clear what residents are getting in exchange for their genetic information.

“A physical is not actually medical care. A physical is actually a medical screening,’’ said Megan Allyse, a researcher at the Mayo Clinic who studies the intersection of genetics, ethics, and health. “So if the physical is being done, but things like return of results or access to follow-up care are not being provided, then there’s an active question of what, if any, benefit that physical is conferring.’’

Rebecca Robbins can be reached at rebecca.robbins@statnews.com. Follow her on Twitter @RebeccaDRobbins. Follow Stat on Twitter @statnews.