Global differences in code quality – any research/meta-analysis available?

Has anyone done a meta-analysis of code quality across different countries? I'm interested in whether there's research comparing code quality at a global level (acknowledging the challenges in defining code quality) to identify potential differences between regions like the USA, Europe, China, and India.

Reading John Ousterhout's 'A Philosophy of Software Design' made me realize how much I missed having a proper software design course in university. This got me wondering about how software design education might vary and impact software quality at national and global levels.