New research from Gothenburg University on solidarity in Sweden backs up evidence from previous studies that ethnic diversity is bad for social cohesion.

Surveying 9,800 randomly selected people, the university’s SOM Institute looked at the degree to which people in Sweden are able to feel a connection with people who differ from themselves.

Researchers found that, outside of their own group, respondents are most inclined to feel an affinity with people whose education vastly differs from their own.

“Most also feel a relatively large affinity with those who have very different political views, a different sexual orientation or whose financial situation differs from their own,” science and technology magazine Forskning reports.

Respondents said they feel the least affinity with people with different ethnic backgrounds, who practice a different religion, or who were brought up in other cultures.

Overall, however, researchers said the study shows that “social cohesion is strong” in Sweden, because 95 per cent of respondents said they feel like a part of society.

The groups which were least likely to profess a sense of belonging to Swedish society were people on low incomes, and people who hold citizenship of nations other than Sweden.

Jesper Strömbäck, professor of journalism and political communication at the University of Gothenburg, said he was surprised the study found social cohesion in Sweden to be so high.

“The increase in income inequality and the refugee crisis has created a polarisation in politics and in the public debate in recent years,” he told Forskning. “Many people had probably expected the research would find that cohesion was lower.”

The SOM Institute’s findings that people feel less solidarity with ethnic groups other than their own add to a growing body of research showing ethnic diversity has a negative effect on societal cohesion.

U.S. researchers who in 2013 showed homogeneous or highly segregated neighbourhoods are almost always more cohesive than those which are diverse, reported that diversity prevents “the formation of dense interpersonal networks that are necessary to promote sense of community”.

Similarly, 2014 research from Australia found diversity had a negative impact on social cohesion and caused residents to “hunker down”, avoiding engagement with the community.

Researchers said their work supports the theory of Robert Putnam, whose U.S. study yielded similar results, that ethnic diversity erodes trust.

And a 2014 study by the University of North Carolina which examined regions across Europe, found that “an increase in immigration is related to a decrease in social trust”.