There’s little doubt that mental illness is a major cause of human suffering around the world. But it may be harder to address than other deep problems like disease or poverty, partly because mental well-being is so difficult to quantify.

That’s what the Mental Health Million project at Sapien Labs, a nonprofit founded in 2016 to study the human mind, is meant to address. The group last month released its second annual Mental State of the World report, surveying over 220,000 people in 34 countries with its Mental Health Quotient (MHQ) questionnaire.

The questionnaire came out of the group’s frustration at the lack of a single, comprehensive scoring tool that aimed to capture the full range of mental well-being across a population, not just in terms of illness or disorders, but on the positive end as well. After reviewing a number of existing clinical tools or questionnaires, they arrived at a list of 47 elements to use as questions in the MHQ scale, which could be filled out as an online questionnaire by respondents in about 15 minutes. The survey is freely available online to anyone who wants to take it, and participants in the study were actively recruited mainly via Facebook and Google ads. (The researchers note that this may not result in a population-representative sample, though the same methodology was used in all countries surveyed.)

These inputs are used to calculate an aggregate score between -100 and +200, with the full range divided into categories on a spectrum from “distressed” to “thriving.” The 47 total elements are also organized into five areas based on what aspect of well-being they focus on — mood and outlook, drive and motivation, social self, mind-body connection, and cognition — with separate scores for each. The MHQ has been validated and shown to give reliable results on retakes, and “negative” scores correlate strongly with qualifying for a DSM-5 diagnosis, and the results are also predictive of productivity.

The initial results of the survey aren’t reassuring.

The kids are not all right

One standout finding was a worrying decline in mental well-being in the 18-24 age bracket. That’s a surprise: Previous mental health surveys — albeit ones that were mostly US-only and employed different measurement tools — tended to show a U-shaped curve of well-being over the course of a lifetime, with the youngest and oldest groups faring best and a dip for the middle-aged.

While concerns about the state of youth mental health have been growing in the US — a new CDC survey found that more than four in 10 adolescents reported feeling “persistently sad or hopeless” — Tara Thiagarajan, the founder and chief scientist at Sapien Labs, told me, “it’s not an isolated issue of one country. It’s a global issue.”

This trend was already present before the Covid-19 pandemic but worsened significantly between 2019 and 2021, with the total percentage of people scoring in the “struggling” or “distressed” range doubling between 2019 and 2021, to 30 percent. Notably, the decline was correlated more closely with the stringency of lockdown measures rather than the direct damage from the pandemic.

The researchers considered various possible causes — income inequality, political instability, civil unrest — but none of these factors has been consistently worsening around the world.

Courtesy of Sapien Labs

One factor is truly universal: rising smartphone use and internet access. Despite longstanding concerns that smartphones and social media exposure harm mental health, especially for young people, existing studies have shown mixed results.

But the researchers behind the Mental Health Million report speculate that the key factor may not be the internet itself but what time spent on the internet replaces. Recent global statistics suggest that people with internet access spend on average seven to 10 hours per day online, which could crowd out in-person interaction that is key to building a strong social self.

Building social skills and relationships requires time and experience. But Thiagarajan believes the youngest generation has “arrived at age 18-24 and college with one-tenth of the expertise in solving social issues, living together, coexisting in productive ways without conflict. And I think a lot of the unrest and conflict may be quite related to that, because at age 18, now you have the same experience of interacting with people as a 7- or 8-year-old had in the past.”

Why well-being matters

If the existing decline in mental well-being among young people was related to internet use crowding out in-person social time, it follows that the isolation of lockdowns would have hit the 18-24 cohort especially hard. And previous studies show that lower mental well-being scores on the country level correlate with higher rates of suicide, sexual violence, and violent assault, especially for the 18-24 age bracket.

The Mental Health Million team hopes that the MHQ will provide a better understanding of this key issue. It’s admittedly imperfect — the questionnaire is only available online, in just four languages (English, Spanish, French, and Arabic), and would mostly have attracted participants who were in a position to see online ads. This population might be unrepresentative in a number of ways; for one, especially in poorer countries, internet users are likely to be the wealthiest and best-educated segment of the population, and differ from the average in other ways.

Even in countries with more ubiquitous internet access, young people who spend the most time on the internet and might thus be hit harder by the resulting negative well-being effects are likely overrepresented; conversely, for older people, the internet-savvy may be ​​better connected and educated than the norm for that age group, which might contribute to the consistently high reported well-being in the 65-plus cohort. Cultural factors could also affect how people interpret survey questions, as well as how they relate to the concept of well-being and mental illness; this makes the patterns found on the country level with cultural indicators more fraught to analyze.

Wealth doesn’t always equal happiness

Countries and cultures seemed to affect mental well-being in other, unexpected ways. Counterintuitively, higher national GDP was correlated in the survey with lower self-reported well-being. The English-speaking countries — the US, UK, Ireland, Canada, Australia, and New Zealand; all developed, rich countries — had the worst average scores. “We were very surprised to see that,” says Thiagarajan.

The report also looked at cultural factors on the country level, employing indicators compiled by the Globe Project and by Geert Hofstede at Maastricht University. Of the factors examined, performance orientation, which measures the extent to which rewards and recognition are based on job performance, had the strongest negative correlation with average MHQ scores in a country — despite the fact that societies high on this dimension tend to be more economically successful, with higher levels of human development.

On the other hand, the factors of higher power distance (cultures that accept an unequal, hierarchical distribution of power), uncertainty avoidance (cultures that emphasize social norms and rules), and in-group or family collectivism (societies that express pride, loyalty, and cohesion within families) are all positively correlated with mental well-being. As the report puts it, “altogether these relationships paint a surprising but consistent picture: a culture where we are each for ourselves and judged and sorted by performance may be good for economic growth but damaging to our collective mental wellbeing.”

Mental Health Million acknowledges that their survey data and report are only a first step, and further research is needed. Their data is available to researchers on request, and about 20 organizations are already working with it in the hope of finding ways to improve worldwide mental well-being. According to Denver Brown, a psychology professor at the University of Texas studying the effects of physical activity and sleep on mental health, “these findings suggest that we can’t take a siloed approach to understanding mental well-being.”

In the past, the mental health effects of policies were hard to measure; when decisions were made about Covid-19 lockdowns, it was nearly impossible to take into account population well-being in the cost-benefit analysis. But the costs to mental well-being are real, and the Mental Health Million project shows that we can’t ignore it.

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