Apple's HealthKit, which launched last year, is a service for people to pull together health and fitness data from their favorite apps. Apple refers to the service as the "beginning of a health revolution."
But the revolution has its limits. When HealthKit first launched, it included everything from blood alcohol tracking to steps. But its comprehensive tracking does not incorporate one important area of health care: mental health. The oversight was spotted by Spotify developer Brian Whitman, who also pointed out that iOS developers can't add categories that aren't already provided.
This isn't the first time that Apple has been called out for failing to incorporate an important metric. In June, the company finally introduced period-tracking, an important feature for its female population.
However, it might not be as easy as you think for Apple to open the floodgates to behavioral health tracking in HealthKit. For one thing, the research is still thin on the ground when it comes to linking metrics collected by a smartphone and mental health.
Mental health experts say that Apple could take a variety of approaches. The company could choose to support users in inputting self-reported data (like mood) to compare that with exercise levels, sleep, and other metrics. Or it could help users detect when they're feeling higher levels of stress and anxiety by tracking heart rate, respiration, or perspiration levels.
"One of the challenges with behavioral health is how to quantify it into a single metric or set of metrics," said Jonathan Palley, cofounder of a startup called Spire, a wearable that aims to measure levels of stress by tracking respiratory levels. "It's a growing, but new field of research."
Mental health experts say that the space has historically been overlooked by tech companies, but that's beginning to change. In recent years, an exploding number of mobile mental health apps have hit the App Store. Some of these apps focus on connecting users with virtual coaches like Lantern. Others, like Ginger.io, analyze data around smartphone usage to try to determine if a user is feeling depressed.
Apple recently acquired a startup called Emotient, which makes use of artificial intelligence technology to sense emotions by analyzing the facial expression of a user.
Arshya Vahabzadeh, a psychiatrist at Massachusetts General Hospital, says these apps have emerged since there are some mental health conditions, like depression and bipolar disorder, which have indicators that can now be tracked. These might include activity, social interactions with others, and varying sleep levels. But it isn't easy to develop an algorithm to understand these changes, and to make any kind of diagnosis.
Moreover, unlike other health conditions like diabetes or heart disease, Apple wouldn't have a huge pool of experts to turn to who understand the digital mental health space. "Apple would need to talk to experts," said Vahabzadeh. "But there aren't that many in this area."
But Vahabzadeh said that if Apple does incorporate mental health tracking into HealthKit, it could prove highly valuable for the field. He sees huge potential for behavioral health researchers to leverage ResearchKit, a service that essentially turns an iPhone into a medical research device.
Apple confirmed that it isn’t currently tracking mental health on HealthKit, and declined to comment on whether it will be added.