Will we ever know if money and relationships make people happy?

Studies suggest richer, older, married people all tend to be happier than their poorer, middle-aged, single counterparts. But is that really the case?

Many happiness studies related to financial status, age and nationality tend to rely too heavily on how people define their own happiness and how they report it, as well as other assumptions made by researchers about what’s normal and what’s extreme happiness, said Kevin Lang, an economics professor at Boston University and co-author of “The Sad Truth about Happiness Scales,” a report distributed this week by the National Bureau of Economic Research.

One person’s happiness is another person’s mild satisfaction. There’s no strict definition. “How people evaluate their happiness differs and how people report their happiness differs across groups,” Lang said. “Saying you’re very happy is different for two groups.” A 94-year-old man may say he is “feeling good,” but he likely has a significantly different threshold for what that means compared to someone years younger than him, Lang said. Measuring happiness isn’t impossible, but it can be highly problematic, he added.

For their research, Lang and Timothy Bond, a professor at the Krannert School of Management at Purdue University in Indiana, reviewed numerous studies on happiness, including the Easterlin Paradox, which suggests happiness rises with income up to a certain point, the “U-Shaped” the theory that people tend to become happier after middle age, and the reported positive impact of marriage and children on happiness.

Government policies and social freedom impact happiness

Other research compares countries and the happiness of people who live there. The World Happiness Report, based on Gallup World Poll surveys, looks at how content people are based on real issues that affect people’s lives, including government corruption, social freedom, economic growth and social safety net.

The most recent report, released earlier this year, ranked Finland as the happiest country and Burundi as the least happiest country. The United States was ranked 18th, with countries such as Denmark, Switzerland, Canada, Australia and Costra Rica listed above.

But the Gallup report asked people to rank their life satisfaction, which they acknowledge is a slightly different concept to happiness. It could be how you rate your best possible life — a measure where European countries come out on top — or how you experience your life through laughing, smiling and enjoyment — a measure where Latin Americans come out as the happiest.

Asking the right questions to assess a subjective concept

Of course, happiness is — by its nature — subjective, but some studies track people’s emotional life over decades. A Harvard study conducted over 80 years found relationships and how happy people are with those relationships have a huge impact on health, and maintaining those relationships could be equally as important as physical health.

That study followed 268 Harvard sophomores beginning in 1938, including President John F. Kennedy, and now includes 1,300 of the original participants’ offspring. In the 1970s, the study also incorporated 456 Boston inner-city residents.

And yet being alone and feeling lonely has been found to be detrimental to a person’s health — arguably, another objective measure of someone’s well-being — and, by extension, a person’s happiness. Research presented at the 2016 American Psychological Association annual conference by Julianne Holt-Lunstad, a professor of psychology at Brigham Young University, found that people with greater social connections had a 50% reduced risk of dying early.

The bigger the sample, the more likely the happiness measurement will be accurate. The first part of Holt-Lunstad’s study analyzed 148 studies, covering 300,000 participants, while the second part of the study involved 70 studies and 3.4 million people in North America, Europe, Asia and Australia concluded that social isolation, loneliness or living alone were all linked to premature death.

Finding a purpose in life and meaningful relationships

One solution to the happiness conundrum: Dig deep for answers. Determining happiness may then come down to assessing all components of life and overall life satisfaction. Elia Gourgouris, a psychologist and author of “7 Paths to Lasting Happiness,” asks his clients to answer a 25-question survey on life satisfaction, which asks participants to rate how accurate various statements are, such as “I know what my purpose in life is” and “I have fulfilling relationships with family and friends.”

After conducting coaching sessions with his clients, they take the survey again to see how their scores have changed. Whether they’re answering questions for a survey or just assessing their own lives, people can become attuned to how happy they truly are with the help of a few steps. In his 30-year career, Gourgouris said becoming happier includes loving yourself, being grateful, continuously learning and living with passion.

He said it’s important to be grateful for what we do have during the good times and the bad. “Happiness doesn’t mean an absence of adversity,” Gourgouris said. He agreed money helps to a degree— under a certain threshold, depending on cost of living and location, people may feel they’re in survival mode, which diminishes happiness — but it isn’t everything.