'Crowd Diagnosis' of STDs Popular but Often Unreliable

Ricki Lewis, PhD

November 05, 2019

Requests for diagnoses of sexually transmitted diseases (STDs) from peers on a major social media platform have recently skyrocketed. Many requests have been for second opinions, according to a research letter published online November 5 in JAMA.

Alicia Nobles, PhD, data scientist in the Division of Infectious Disease and Global Public Health at the University of California, San Diego (UCSD), and colleagues examined conversations on Reddit. The researchers focused on a large "subreddit" that hosts a health forum dedicated to STDs (r/STD). People share "stories, concerns and questions" and photographs.

One example from the article: "Help! What is this? In the past month I have developed these papules on my butt close to my vagina. Normally my skin is very clear. Is this herpes?!"

A subreddit is a peer group, not an online tool through which people with medical training provide opinions, such as CrowdMed. "A crowd diagnosis is when people turn to strangers on social media to get a diagnosis," John Ayers, PhD, also from UCSD, who is co–lead author of the study with Nobles, told Medscape Medical News.

Peer medical advice delivered via social media has not been well studied. The researchers chose to investigate STDs because of the public interest.

"We assume everyone turns to Dr Google for all of their health concerns. But people also want a sense of connection. The reason social media sites are so popular is that they offer real interactions with real people. For those same reasons, some may choose to seek out medical help on social media platforms," said Nobles.

The Hockey Stick of STD Interest

The researchers considered all posts from r/STD's debut in November 2010 through February 2019. Three of the investigators coded answers to questions from a random sample of 500 posts:

  • Did a post request a crowd diagnosis?

  • If so, did the request seek a second opinion after the person had seen a healthcare professional?

  • Did the post include an image?

  • Did the person receive a reply?

  • How long did it take to get an initial reply?

The graph of the time trend for posting on r/STD resembles the famous global warming hockey stick: straight up.

Of 16,979 total posts, eight were in November and December 2010; 2478 were in 2017; 3375 were in 2018; and 908 were in January and February 2019. The number of posts per month hovered near 100 in 2012, reached 200 to 300 in 2018, and hit 500 in January 2019.

People sought help. Fifty-eight percent of the posts requested a crowd diagnosis, and 31% included an image of the affected area of skin.

People answered. Eighty-seven percent of posts requesting a crowd diagnosis received a reply. The mean number of responses was 1.7, and the median time to first response was 3.04 hours; 79% of the requests were answered within a day.

"We found 20% of crowd-diagnosis requests were made after already obtaining a physician diagnosis. On one occasion, a patient had received an HIV diagnosis but turned to the crowd to be convinced the doctor was wrong," Ayers said. The researchers assumed the physician diagnosis of HIV had been accurate.

Conclude the researchers, "requests for crowd-diagnoses were frequent, with most receiving a reply within hours, and many of these requests were for second opinions after obtaining an original diagnosis from a health care professional."

Maximizing the Value of Crowd Diagnosis

Studying crowd diagnosis can be an important tool for healthcare planning, said Ayers. "We could identify what conditions and what types of information the public is willing to share and build out evidence-based resources to match those needs. No one would have expected that the public was willing to share images of their you-know-what to obtain STD diagnoses on social media," he told Medscape Medical News.

But diagnosis by peers, whatever the format, can pose risks. Ayers suggested that medical professionals partner with social media companies to combat the spread of misinformation or misdiagnoses.

"Social media platforms could be improved to facilitate more reliable and actionable crowd diagnoses. For instance, experts could moderate requests for crowd diagnoses, resulting in social media being a vehicle to connect the public to professional healthcare," Ayers said. That would edge r/STD more toward the CrowdMed model.

But the STD subreddit differs substantially from CrowdMed, according to Hardeep Singh, MD, MPH, chief of the Health Policy, Quality and Informatics Program, Center for Innovations in Quality, Effectiveness and Safety at the Michael E. DeBakey Veterans Affairs Medical Center and the Baylor College of Medicine, Houston, Texas. He led a study of CrowdMed that was published in 2016 in the Journal of Medical Internet Research.

"CrowdMed is an organized platform for crowd-sourced diagnosis where people sign up to provide others with medical opinions. With a small fee, patients anonymously answer a comprehensive set of medical questions and upload relevant test results and images. Suggestions follow where diagnoses are ranked in decreasing order of relative popularity determined by prediction algorithms," Singh explained.

Patients who use CrowdMed tend to have undiagnosed illnesses; some have seen more than five physicians. Singh's study found that 208 of the 387 (58%) participating diagnostic detectives had worked or studied in the healthcare industry, including 36 physicians and 56 medical students.

"This JAMA piece seems to be about an endeavor where people share or show personal details to get a quick opinion from peers on social media who may have had similar issues. While peer support groups can have value, this may be considered somewhat of a Wild West of diagnosis, much more informal than CrowdMed," Singh said.

He cited as possible motivations for people to post at r/STD concerns about cost and accessibility of healthcare; mistrust of diagnoses from providers; and the speed of an answer. "The anxiety of waiting to see someone can be unbearable compared to a possibly correct answer from a stranger when you are looking for some reassurance," Singh said.

Potential harms of crowd diagnosis are an incorrect diagnosis and delays in testing or treatment. "As we suggested for CrowdMed, such second-opinion-type platforms need evaluation and validation," Singh said.

Limitations of the study are that it investigated a single social media platform for a single medical condition and that it did not probe characteristics of participants, the accuracy of the diagnoses, and whether individuals acted on the advice that was provided.

The researchers and Singh have disclosed no relevant financial relationships.

JAMA. Published online November 5, 2019. Abstract

Follow Medscape on Facebook, Twitter, Instagram, and YouTube


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.