Online symptom presentation key for self-diagnosing patients

How symptoms are listed in an online disease risk assessment can dramatically affect whether a user thinks he or she has that disease.

In particular, patients who check off a consecutive list of symptoms are more likely to think they have a disease than if their symptoms are nonconsecutive, according to an intriguing new study by researchers from Arizona State University, the University of California-Irvine, Ono Academic College and the University of Warwick.

The study, "Effects of Symptom Presentation Order on Perceived Disease Risk," shows that patients are strongly affected by what they perceive as a "streak" of symptoms--symptoms they have that are listed one right after the other in an online checklist. When the individual' symptoms are more random--varied throughout the checklist--people are less likely to assume they have the condition, the study found.

"Given the human tendency to ascribe meaning to streaks, reading about multiple general symptoms consecutively [as commonly happens] may heighten people's perception of their risk of disease," the study's authors say.

Participants also were most susceptible to the "streak" theory when the checklist started out with general symptoms, and then moved to more specific symptoms, the study shows.

It's a quixotic finding, but one that could be important in a world where patients increasingly use Internet health information to diagnose themselves, the authors indicate. The study's findings are critical for anyone who publishes health risk assessments online--health providers, app developers and online health publishers. After all, as pointed out by an article in the Huffington Post, a Wolters Kluwer Health survey published last year found that  46 percent of physician respondents used Google and Yahoo to help diagnose and treat their patients.

There are two ways to handle the "streak" misperception proactively, the authors say. If a risk assessment is meant to encourage the public to get early screening for an illness, the list should start with general symptoms, and move on to the more rare. But if the goal is to prevent overreaction to a rare disease, listing the rarest symptoms first may be the way go, the authors say.

To learn more:
- read the Psychological Science abstract
- check out the Huffington Post's coverage
- get detail from the Association for Psychological Science announcement