Emojis could be used to live monitor the progress of cancer patients, according to new research.
Positive and negative reactions, recorded using an app on Apple Watches and iPhones, could be used by doctors to see if patients need help in between appointments, a clinician has said.
The feedback would enable cancer sufferers to receive more immediate support for side effects of their treatment, or those who are doing well can avoid unnecessary travel.
Dr Carrie Thompson, from the Mayo Clinic, Rochester, Minnesota, will present research on the feasibility of emoji scales to record the quality of cancer patient life at the American Society of Clinical Oncology (ASCO) annual meeting in Chicago.
"We think there's a lot of potential for these faces, because they cut across a lot of barriers," she told the Press Association.
"They don't require any particular language, they are universal, they don't require a certain education level."
The study asked 294 cancer patients to complete either a survey or emoji scale using technology to record how they were feeling.
Significant links were found in the effectiveness of recording using the traditional paper method and technology.
Dr Thompson said the study proves the technology is a feasible way of monitoring patients and could prove useful in future cancer care.
"Emojis are fun and it's a cool way to communicate, but what it really comes down to is improving patient care," Dr Thompson said.
"If somebody is feeling poorly we want to know about that at the time so we can provide some symptom relief or advice, as opposed to two weeks later."