How useful is it, really, to know thyself? The idea that self-insight is good for us dates all the way back to the inscriptions on ancient Greece’s Temple of Apollo in Delphi. It is still popularly assumed that people with a clear view of themself and their abilities are better off—that they feel better, have more satisfying relationships and are more successful. But when psychologists have tested that premise, they haven’t found much strong empirical evidence of the benefits of self-insight for well-being.

An intriguing new study recently added provocative findings to this long-standing debate. It tested five of the most common hypotheses on the connection between self-insight and psychological adjustment. Does self-knowledge really lead to higher satisfaction? Is it maybe more productive to just think positively—even if a little overconfidently—about one’s abilities? Or could it be that those with the highest abilities will be optimally adjusted? The study, published in July in Nature Human Behaviour, found support for none of these ideas.

Instead it tentatively indicated that it is people with the biggest gap between their abilities and their view of themself who say they have the highest levels of satisfaction with their life, career and relationships. “People who report being more adjusted are those who have a combination of relatively lower true abilities and actual higher views of themselves,” says Stéphane Côté, a social psychologist at the Rotman School of Management at the University of Toronto and an author of the paper.

Beyond its unanticipated findings, the new study is notable for how it was conducted. It was a registered report, a new and still relatively rare process that fundamentally shifts the way scientific research is published by front-loading peer review into the planning stages of a study and accepting that study, in principle, for publication before any data have been collected, regardless of the result. Such an approach is expressly intended for confirmatory research comparing competing hypotheses.

By that criterion, the self-insight study was an excellent candidate. It was one of the first two registered reports in Nature Human Behaviour. Both appeared in the same issue, along with an editorial on the importance of this new way of doing science. Traditionally, it is mostly “significant” results, meaning those that confirm a hypothesis at a level above statistical significance, that get published. That phenomenon has led to a concern that too much scientific research is left in file drawers and never submitted to a journal, biasing the perception of what is known. “We strongly believe that when the question is important and the methods robust, the results will be important no matter what they are,” the authors of the editorial wrote.

“This is a very important piece of work,” says psychologist Mitja Back of the University of Münster in Germany, adding that it showcases the advantages of registered reports. (Back served as a reviewer for that study and helped to strengthen the statistical analysis but was otherwise not involved.) “The paper,” he says “provides one of the very few direct tests of the assumption that individual differences in self-insight are related to adjustment outcomes.”

Others who investigate similar questions found the results intriguing. “This is fascinating work,” says social psychologist Cameron Anderson of the Haas School of Business at the University of California, Berkeley, who wasn’t involved in the new research. “Most people would guess—and many interventions are built upon the assumption—that knowing how smart and skilled you are benefits you in the long run. But this casts doubt on that assumption.”

Rotman’s graduate student Joyce He, who led the study, and Côté recruited more than 1,000 people online. Participants completed itemized tests of cognitive and emotional abilities and then reported how many items they thought they answered correctly. He and Côté recorded the actual number of items on each test and the number of items individuals thought they got right, searching for any disparities between their evaluation of their performance and how they actually did. Then, over the following week, participants filled out a daily diary survey. “We asked them to reflect on how satisfied they were with their life, with their career, with relationships in general,” He says. By extending the survey over a week, she adds, she and Côté avoided the distortion that might come with someone having a particularly good or bad day.

Previous studies on self-insight had been limited, in part, by statistical techniques. Most researchers have employed “difference scores,” measures of the gap between true and self-perceived ability, but they have been criticized because they conflate the original variables, which leads to ambiguous interpretations of the results. Instead He and Côté used a technique called polynomial regression, which represents a more complex statistical model that preserves the original variables. One of the benefits of the registered report process, they say, was the extensive guidance they got on how to use polynomial regression effectively. Both believe that early feedback made their paper stronger, and they are now committed fans of the registered reports approach. “It’s revolutionizing the way science is done and the kind of findings people are reporting,” Côté says.

It is quite possible that in the past, a study like this one would not have been published because the statistical analysis could not confirm what was initially proposed. As it is, the unexpected result showing that considerable self-delusion is helpful while a realistic perspective is not, which He and Côté are calling “beneficial self-enhancement,” must be regarded as preliminary because they hadn’t put it forth as one of their hypotheses. They are at work on follow-up studies and have some early confirmatory results, but nothing has been published yet.

Importantly, even if it is confirmed that self-insight does not provide much benefit in psychological adjustment, a clear view of one’s abilities might still be an important element in job performance or other areas. Psychologist Elizabeth Tenney, who studies organizational behavior at the University of Utah, doesn’t think that all job reviews and student evaluations should leave out feedback on strengths and weaknesses just yet. Regarding the study, she says, “They didn’t give [subjects] self-insight and then watch what happened over time.” Côté agrees. “Nothing should be based on a single paper,” he says.

What is clear is that registered reports allow scientists a clearer perspective on their own work. “Scientists are human,” Tenney says. “We immediately will rationalize and find explanations for results. I love that [this process] ties the authors hands to do the analyses that they set out to do. This is the way science is supposed to work.”