Big Tech is moving into health care. Google has announced an intention to buy Fitbit and is also poised to collect health data on tens of millions of patients through a deal with St. Louis-based hospital chain Ascension. InMarch, Amazon, Berkshire Hathaway, and J.P. Morgan announced their health venture, Haven. Apple is using its devices to help academics run studies with millions of participants. And Microsoft and IBM are using artificial intelligence and machine learning to help researchers develop better cancer treatments.

The use of digital technology in health care has enormous promise, to be sure. But The Wall Street Journal’s coverage of Google’s Project Nightingale also revealed a potential dark side to the projects. Ascension, it noted, “also hopes to mine data to identify additional tests that could be necessary or other ways in which the system could generate more revenue from patients, documents show.”

That detail raises a key question that’s largely overlooked in our health care debates: Should the drive to maximize corporate revenues determine how health information technology develops and becomes integrated into medical practice, or should that be determined by medical science and the public?

Google, Amazon, Apple, and Microsoft could use their technical expertise to improve human health, but that is not their purpose. The purpose of these corporations is to maximize shareholder value, and that can lead them to use these technologies to very different ends.

For example, digitized health care databases derived from electronic medical records can be used by medical researchers to find out which medical procedures work better than others. On the other hand, the same data can be used to boost revenues by finding new candidates for unnecessary tests and screenings, unproven therapies, and avoidable surgeries. Studies show that up to 28 percent of all health care spending in the United States goes for various forms of overtreatment, and the billions in resulting revenues fattens the bank accounts of health care executives and shareholders.

Today’s health IT infrastructure is already highly monopolized. For example, just two corporations, Epic and Cerner, now control 85 percent of the market for electronic health records (EHRs) used by hospitals with more than 500 beds, according to a report from KLAS Research. Epic alone reportedly holds the health records of roughly 200 million Americans.

Despite - or perhaps because of - their large market share, these EHR giants produce software that isn’t very good. An investigation by Kaiser Health News in March found EHR systems are extremely frustrating for professionals to use and can be rife with errors that can lead to dangerous - and sometimes fatal - results for patients.

Another, bigger problem is that patients’ data might eventually be used for corporate control and exploitation.  A big part of the promise of EHRs is that the data they generate can be anonymized and collected in a searchable database that becomes an invaluable tool for advancing medical science and practice. But when so much of that data is collected by profit-maximizing, monopolists, much of the promise of digital medicine is lost.

An alternative path exists. In the 1970s, the Veterans Affairs Administration (VA) developed VistA, an open-source code system that was the country’s first EHR system. Open-source code broadly describes code that users can take and modify for themselves. In contrast, proprietary, closed-source programs such as Epic’s often do not allow users to alter the underlying program. Instead, medical providers often have to report a bug, as opposed to fixing it themselves.

As Open Markets’ Policy Director Phil Longman wrote in 2009, the open-source nature of VistA “allowed almost anyone with a good idea at the VA to innovate.” In his 2010 book about the VA’s health care system, Best Care Anywhere, Longman said, “[T]he VA software’s code has been continually improved by a large and ever-growing community of collaborating, computer-minded health-care professionals.”

The VA’s collection of veterans’ health information also helped the agency and outside researchers study the safety of different drugs and treatments and the performance of different doctors. Dr. Nancy Anthracite, director and president of WorldVistA, a non-profit group that facilitates the adoption of the VA’s open-source code by other health care providers, told Politico in 2017, “I don’t know if there even is an EHR out there with data comparable to the longitudinal data that VistA has about veterans.”

Open-source code doesn’t mean abolishing intellectual property or competition. For example, private companies such as Medsphere have built their business around installing and customizing VistA, similar to how Red Hat sells an operating system based on the open-source Linux systems.

Nor does open-source code mean that patient records are open for all to see. The open nature of VistA actually makes it harder for hackers to steal records because a decentralized community of programmers scours the source code for bugs and weak spots.

Massachusetts Senator and presidential candidate Elizabeth Warren has promised that her administration would appoint antitrust enforcers to investigate “the health records market, especially in the hospital space.” That would be a strong step. But in addition to antitrust measures, America needs to make a serious commitment to building a health IT infrastructure that is openly shared and directed by science and the public interest.