We're not sure what any of this "means", but a study done by the English Journal of Epidemiology and Community Health has concluded that Bangladeshi girls living in the UK who wear traditional Bangladeshi clothes during their childhood are less likely to suffer from mental health problems as they get older than those who wear a mixture of traditional and "modern" English/North American styles.[UPI]
@Archetype: Yeah, yeah — see, I'm not trying to hound you or anything, I'm just slightly skeptical about how much we want to consider traditional clothes as "having that decision made for you" any more than modern clothes do. Traditional clothes are not exactly utilitarian, like jumpsuits or uniforms, especially in the subcontinent! Wearing a sari doesn't magically exempt you from all systems of beauty and fashion, it just means you're a part of slightly different ones. (Granted, I can see arguments that the ones you become a part of might be a tad less stressful than the modern Anglo one.)
I'd tend to assume, with R-star, that this probably has a lot more to do with what kind of community you're coming from, whether it's traditionalist or assimilating, etc. — something the clothes are going to be correlated with as well.