By Jacqueline Howard, CNN

(CNN) -- A pair of public health experts has called for Facebook to be more transparent in the way it screens posts for suicide risk and to follow certain ethical guidelines, including informed consent among users.

The social media giant details its suicide prevention efforts online and says it has helped first responders conduct thousands of wellness checks globally, based on reports received through its efforts. The authors said Facebook's trial to reduce death by suicide is "innovative" and that it deserves "commendation for its ambitious goal of using data science to advance public health."

But the question remains: Should Facebook change the way it monitors users for suicide risk?

'People need to be aware that ... they may be experimented on'

Since 2006, Facebook has worked on suicide prevention efforts with experts in suicide prevention and safety, according to the company.

In 2011, Facebook partnered with the National Suicide Prevention Lifeline to launch suicide prevention efforts, including enabling users to report suicidal content they may see posted by a friend on Facebook. The person who posted the content would receive an email from Facebook encouraging them to call the National Suicide Prevention Lifeline or chat with a crisis worker.

In 2017, Facebook expanded those suicide prevention efforts to include artificial intelligence that can identify posts, videos and Facebook Live streams containing suicidal thoughts or content. That year, the National Suicide Prevention Lifeline said it was proud to partner with Facebook and that the social media company's innovations allow people to reach out for and access support more easily.

"It's important that community members, whether they're online or offline, don't feel that they are helpless bystanders when dangerous behavior is occurring," John Draper, director of the National Suicide Prevention Lifeline, said in a press release in 2017. "Facebook's approach is unique. Their tools enable their community members to actively care, provide support, and report concerns when necessary."

When AI tools flag potential self-harm, those posts go through the same human analysis as posts reported by Facebook users directly.

The move to use AI was part of an effort to further support at-risk users. The company had faced criticism for its Facebook Live feature, with which some users have live-streamed graphic events including suicide.

In a blog post, Facebook detailed how AI looks for patterns on posts or in comments that may contain references to suicide or self-harm. According to Facebook, comments like "Are you OK?" and "Can I help?" can be an indicator of suicidal thoughts.

If AI or another Facebook user flags a post, the company reviews it. If the post is determined as needing immediate intervention, Facebook may work with first responders, such as police departments to send help.

Yet an opinion paper published Monday in the journal Annals of Internal Medicine claims that Facebook lacks transparency and ethics in its efforts to screen users' posts, identify those who appear at risk for suicide and alert emergency services of that risk.

The paper makes the argument that Facebook's suicide prevention efforts should align with the same standards and ethics as would clinical research, such as requiring review by outside experts and informed consent from people included in the collected data.

Dr. John Torous, director of the digital psychiatry division in Beth Israel Deaconess Medical Center's Department of Psychiatry in Boston, and Ian Barnett, assistant professor of biostatistics at the University of Pennsylvania's Perelman School of Medicine, co-authored the new paper.

"There's a need for discussion and transparency about innovation in the mental health space in general. I think that there's a lot of potential for technology to improve suicide prevention, to help with mental health overall, but people need to be aware that these things are happening and, in some ways, they may be experimented on," Torous said.

"We all agree that we want innovation in suicide prevention. We want new ways to reach people and help people, but we want it done in a way that's ethical, that's transparent, that's collaborative," he said. "I would argue the average Facebook user may not even realize this is happening. So they're not even informed about it."

In 2014, Facebook researchers conducted a study on whether negative or positive content shown to users resulted in the users producing negative or positive posts. That study sparked outrage, as users claimed they were unaware that it was even being conducted.

The Facebook researcher who designed the experiment, Adam D.I. Kramer, said in a post that the research was part of an effort to improve the service -- not to upset users. Since then, Facebook has made other efforts to improve its service.

Last week, the company announced that it has been partnering with experts to help protect users from self-harm and suicide. The announcement was made after news around the death by suicide of a girl in the United Kingdom; her Instagram account reportedly contained distressing content about suicide. Facebook is the owner of Instagram.

"Suicide prevention experts say that one of the best ways to prevent suicide is for people in distress to hear from friends and family who care about them. Facebook is in a unique position to help because of the friendships people have on our platform -- we can connect those in distress with friends and organizations who can offer support," Antigone Davis, Facebook's global head of safety, wrote in an email Monday, in response to questions about the new opinion paper.

"Experts also agree that getting people help as fast as possible is crucial -- that is why we are using technology to proactively detect content where someone might be expressing thoughts of suicide. We are committed to being more transparent about our suicide prevention efforts," she said.

Facebook also has noted that using technology to proactively detect content in which someone might be expressing thoughts of suicide does not amount to collecting health data. The technology does not measure overall suicide risk for an individual or anything about a person's mental health, it says.

The National Suicide Prevention Lifeline said in a written statement emailed to CNN on Monday that the organization "has long shared the message that everyone can be active in suicide prevention, and that we can all be the one to help someone in crisis. In keeping with this message, the Lifeline has advised Facebook on the development of their suicide prevention reporting tools and guidelines."

What health experts want from tech companies

Arthur Caplan, a professor and founding head of the division of bioethics at NYU Langone Health in New York, applauded Facebook for wanting to help in suicide prevention but said the new opinion paper is correct that Facebook needs to take additional steps for better privacy and ethics.

"It's another area where private commercial companies are launching programs intended to do good but we're not sure how trustworthy they are or how private they can keep or are willing to keep the information that they collect, whether it's Facebook or somebody else," said Caplan, who was not involved in the paper.

"This leads us to the general question: Are we keeping enough of a regulatory eye on big social media? Even when they're trying to do something good, it doesn't mean that they get it right," he said.

Several technology companies -- including Amazon and Google -- probably have access to big health data or most likely will in the future, said David Magnus, a professor of medicine and biomedical ethics at Stanford University who was not involved in the new opinion paper.

"All these private entities that are primarily not thought of as health care entities or institutions are in position to potentially have a lot of health care information, especially using machine learning techniques," he said. "At the same time, they're almost completely outside of the regulatory system that we currently have that exists for addressing those kinds of institutions."

For instance, Magnus noted that most tech companies are outside of the scope of the "Common Rule," or the Federal Policy for the Protection of Human Subjects, which governs research on humans.

"This information that they're gathering -- and especially once they're able to use machine learning to make health care predictions and have health care insight into these people -- those are all protected in the clinical realm by things like HIPAA for anybody who's getting their health care through what's called a covered entity," Magnus said.

"But Facebook is not a covered entity, and Amazon is not a covered entity. Google is not a covered entity," he said. "Hence, they do not have to meet the confidentiality requirements that are in place for the way we address health care information."

HIPAA, or the Health Insurance Portability and Accountability Act, requires the safety and confidential handling of a person's protected health information and addresses the disclosure of that information if or when needed.

The only protections of privacy that social media users often have are whatever agreements are outlined in the company's policy paperwork that you sign or "click to agree" with when setting up your account, Magnus said.

"There's something really weird about implementing, essentially, a public health screening program through these companies that are both outside of these regulatory structures that we talked about and, because they're outside of that, their research and the algorithms themselves are completely opaque," he said.

'The problem is that all of this is so secretive'

It remains a concern that Facebook's suicide prevention efforts are not being held to the same ethical standards as medical research, said Dr. Steven Schlozman, co-director of The Clay Center for Young Healthy Minds at Massachusetts General Hospital, who was not involved in the new opinion paper.

"In theory, I would love if we can take advantage of the kind of data that all of these systems are collecting and use it to better care for our patients. That would be awesome. I don't want that to be a closed book process, though. I want that to be open with outside regulators. ... I'd love for there to be some form of informed consent," Schlozman said.

"The problem is that all of this is so secretive on Facebook's side, and Facebook is a multimillion-dollar for-profit company. So the possibility of this data being collected and being used for things other than the apparent beneficence that it appears to be for -- it's just hard to ignore that," he said. "It really feels like they're kind of transgressing a lot of pre-established ethical boundaries."