If you've ever rubbed elbows in an Irish pub, visited a Danish city where people ride community-owned bicycles, or witnessed an American neighborhood coming together after a tragedy, you know there's more to a country's wealth than money can buy.

Until now, though, there hasn't been a systematic way to study countries' "subjective well-being" — the psychologist-developed construct that captures the way citizens experience quality of life, beyond such established measures as gross domestic product, health statistics and educational outcomes.

A new development promises to change that. In March, an international economic think tank representing 34 developed democratic nations, including the United States — known as the Organisation for Economic Co-operation and Development, or OECD — issued guidelines for member nations on how to measure these internal cognitions, feelings and appraisals.

The guidelines offer advice to countries' statisticians, policymakers and academicians on creating their own subjective well-being measures and provide a set of core measures that can be used right away for internal and cross-national analyses.

The move is an important step toward better understanding the factors that make some countries great places to live in terms of human happiness and others less desirable, and to help shape policy accordingly, says Edward Diener, PhD, the University of Illinois psychologist who helped launch the study of subjective well-being. 

"The OECD plays a pivotal role in terms of which statistics countries collect and how they collect them," says Diener, who sat on the advisory committee for the guidelines. "The fact that they issued this very positive report [on the importance of including these measures in international data collection] is huge."

The OECD chose to issue the guidelines because the evidence is now sufficiently strong for subjective well-being to be validly measured, notes economist Conal Smith, a section head in the OECD's statistics directorate.

"A lot of policies are based on goals that aren't specifically economic, but until now, our ability to analyze them quantitatively and understand them in a scientific way has been quite limited," he says. "Now that we are gaining this ability, the OECD felt it was the right time to begin creating some international harmonization of these measures, so that countries could start collecting more comparable data."

Diener and other psychologists have studied subjective well-being for more than three decades. In 2000, Diener called for the phenomenon to be measured on a national level in an article in the American Psychologist. Since then, he and other leading psychologists, including Daniel Kahneman, PhD, of Princeton University, and Martin E.P. Seligman, PhD, of the University of Pennsylvania, have added theory and data to the topic, arguing that such measures can add both richness and objectively useful information to public policy discussions and goals. In the last few years, they've also worked hard to validate the measures.

The OECD guidelines include questions in three areas: life evaluation, which captures people's cognitive impression of the quality of their lives; affect, or how people feel at a given point in time; and "eudaimonia," or contentment, which examines people's sense of meaning and purpose.

Such data can be useful by themselves, in relation to other data, and as comparison points with other countries or on specific factors within countries, Diener notes. On the individual level, people who score high on subjective well-being are likely to live longer, do better in the workplace and have lower health-care costs, for example. On a national scale, subjective well-being is associated with high social capital — or citizens' propensity to trust and respect one another — and with lower crime rates.

Subjective well-being data can also have predictive value, Smith says. Over the past decade, for instance, the human development index — a composite measure of life expectancy, educational attainment and income — rose throughout North Africa and the Arab world. But about 18 months before the Arab Spring began in 2010, subjective well-being scores in those countries began to plummet, and they dropped most significantly in some of the first countries to take part in the uprising, Tunisia and Egypt.

"It's clear that these measures pick up things that matter to people that other indicators simply don't catch," says Smith.

The OECD action represents an opportunity for psychologists to share data that are relevant to international public policy not only in this one aspect of psychological research, but in other areas of the science as well, Diener adds. 

"Ideally, such data would include questions in all of the policy-related areas that psychologists study — social, personality and developmental." 

For a copy of the guidelines, visit OECD.

Tori DeAngelis is a writer in Syracuse, N.Y.