The author's did find that people with lower incomes tended to live in areas with more traffic noise and we know that socio-economic status is also a predictor for strokes, but they didn't control for that in this study and it could be less about the noise and more about other lifestyle factors
I didn't even have time to get angry about the fact that, poverty is not a fucking lifestyle factor, because I was so horrified that they didn't control for class. What were these researchers doing? And why did such a ridiculous study get international news coverage? Why was 2 minutes 19 seconds of so the lives of Radio NZ listeners wasted with this drivel?
If you're researching people's bodies - no scratch that - if you're researching people and you don't take into account that people have different access to resources, then your research has no meaning and no value. And if it is picked up and promoted and treated as interesting, that's because it's lack of truth makes it a useful ideological tool.