The concept of “grit” has risen to prominence recently on a wave of publicity for Angela Duckworth’s book, Grit: The Power of Passion and Perseverance. The idea of grit is that success is about more than just natural talent—finding something you’re passionate about and persevering in it is more important than how talented you are to start out with. This can help to explain why people who are highly talented aren’t always successful.

That grit is as important as talent is an inspirational message—in part. One common criticism is that this message leads to a painful amount of self blame in, and prejudice against, people who fail at something. But the concept has snowballed into a simplistic, self-help wrecking ball, and even Duckworth is concerned about how far the idea is being taken.

But is the concept valid to start with? There's a study due to be published in the Journal of Personality and Social Psychology, and an early version has been made available by lead author Marcus Credé. The authors take a close look at the results of multiple studies on grit, pointing out some important problems with the idea. Apparently it doesn’t make as big a difference in success as the hype claims, and it doesn’t seem to be all that different from a concept we’ve known about for a long time: conscientiousness.

The big question, really, is whether grit is something that can be changed, and the jury is still out on that matter.

How much is heart, how much is smarts?

Grit sits alongside factors like intelligence, anxiety, conscientiousness, and others as a potential explanation for why some individuals do better than others in education and areas like sports. Studying it is complicated because there are so very many other interrelated factors that need to be taken into account, from socioeconomic status to personal experiences.

If you want to change people’s environments to allow them to reach their full potential, you need to establish just how much traits like intelligence and conscientiousness depend on genetics and how much they can be altered by tweaking environmental factors and personal experiences. Current evidence suggests that intelligence—which is heavily influenced by genetics but has a malleable component—is a strong contributing factor to success. Still, there’s a big gap left to be filled by other traits.

Grit is a powerful and attractive candidate for filling in this gap, because it implies that success is as much about determination and perseverance as it is about talent. The idea has been taken to heart by various educational bodies. It's being highlighted as a promising avenue for intervention by the US Department of Education, and it has been planned as a form of assessment in some schools beginning in 2017.

Even Duckworth thinks that’s jumping the gun. As Credé and his colleagues point out in their paper, there’s a risk of wasting substantial resources if so many educational bodies put their weight behind an idea that turns out to be ill-defined and not very useful.

The nitty-gritty of grit

Credé and colleagues analyzed 88 experiments on grit reported in 73 papers, using data from 66,808 individuals. The results of their meta-analysis raise a few important questions about grit.

The tests that assessed grit break down into two sub-concepts: perseverance (the tendency to continue working hard in the face of setbacks) and consistency (directing that hard work toward a single goal over a long period of time). Credé and colleagues note that it’s not actually clear whether these two traits operate in tandem—whether they're components of an overall trait.

In fact, the meta-analysis suggests that while perseverance seems to play a reasonably substantial role in predicting measures of success (like GPAs), consistency doesn’t seem to be nearly as important. Perseverance on its own actually turned out to be a better predictor than grit, they write.

A bigger problem is the degree to which grit is related to success. In her 2013 TED talk, Duckworth says that “One characteristic emerged as a significant predictor of success. And it wasn’t social intelligence. It wasn’t good looks, physical health, and it wasn’t IQ. It was grit.” This flies in the face of a large body of evidence that finds a very strong role for intelligence in certain forms of success, explaining about half of people’s differences in “performance in academic and work settings,” the authors write.

The meta-analysis found that grit does correlate, modestly, with academic performance and drop-out rates. The difference is small, but, as the authors point out, even small differences can have a big impact. For example, a small change to college drop-out rates—as little as a single percentage point—could change the lives of thousands of students. Duckworth told NPR that she doesn’t disagree with this and that the impact of grit is in the “small-to-medium” range. Perhaps the TED talk was just performance hyperbole.

But Credé and colleagues question whether grit is really news at all. For a long time, psychologists have been talking about conscientiousness, one of the “Big Five” personality traits that seems to do some reasonably heavy lifting in explaining the differences among people. Conscientiousness is a trait that has a number of different facets, such as self control and a striving for achievement. Some of the items on the scale that assesses grit are strikingly similar to questions used to assess conscientiousness, the authors point out.

Fittingly, they found a stunning correlation between grit and conscientiousness: 84 percent. What’s more, both grit and conscientiousness correlate to a similar degree with other measures, like high school and college GPAs. There’s a risk that grit might just be “old wine in new jars," Credé and colleagues write.

Duckworth isn’t too concerned about this—she thinks of grit as a “member of the more broadly defined conscientiousness family,” she told Ars in an e-mail. The importance of grit in explaining sticking power, as in drop-out rates, is something that can’t be predicted as well by conscientiousness, she says. And the meta-analysis tentatively points out a similar finding: “The assessment of grit may be useful in settings in which retention is problematic,” Credé and colleagues write.

Can you get grittier?

There are some important questions left open by the meta-analysis. For instance, grit is tested by asking people to self-assess their perseverance and consistency, and there’s a strong possibility that people aren’t very good at answering these questions accurately. They might overestimate or underestimate their grit based on their self-awareness or the norms of their environment—for instance, in high-achievement schools, pupils may think of themselves as lazier than the norm.

It’s also not clear whether grit applies differently in different domains. For example, it might make only a small difference to school or college results, but it could make a big difference to domains like music or sport. It’s important for researchers to figure out where it does and doesn’t matter, Credé and colleagues write.

The big question that motivates a lot of this is whether it’s possible to get grittier, and that’s also a big gap in the evidence here. We don’t know whether it’s a skill that people learn or a trait—like neuroticism—that forms part of a personality. While researchers work on figuring that out, we probably shouldn't put too many eggs in the grit basket. “Schools and colleges have limited resources to devote to interventions and are likely to be best served by focusing those resources on variables that have been demonstrated to be … responsive to interventions,” Credé and colleagues argue. Duckworth agrees: "I feel like the enthusiasm is getting ahead of the science."

Journal of Personality and Social Psychology, 2016. DOI: 10.1037/pspp0000102 (About DOIs).