It says Denmark and Finland have 24 percent single parent households which lineup with Caucasians in America at around 25% and Sweden is at 34% which is quite a bit higher then the same racial group in America. France is also on the rise and was last reported at 23% in 2023. Seems like they match up with their demographic here in the states. Of the bigger countries only Germany and uk had lower rates at around 14-15%.
A strong cultural difference is how much fathers participate in raising their children. A single mother with her former husband actively engaged in child rearing and discipline will likely have a better chance of raising law abiding children.
Behavioral studies could develop statistical models of degrees of fatherhood in children’s lives resulting in those children’s success as adults. That’s not my field of expertise but it doesn’t take a PhD to see the results.