I wonder if they controlled for... why people choose to live where they live. I.e., this wasn’t an RCT; they could just assign people to live near highways or not. So the people who are living near highways are there for a reason.
Are residences near highways, perhaps farther from certain other things, like city centres? Such that a certain type of person (people with pre-existing [perhaps subclinical] mental issues of the type that might make them want to avoid people) would be drawn to live in these residences more than others?
To me, “living near a highway” sounds a lot like a euphemism for “living in the middle of nowhere”, since by definition all arterial roads connecting “somewhere” to “somewhere” through “nowhere” are highways. If you live somewhere isolated that’s accessible at all by road, and you don’t have the budget to build your own long stretch of lane out from the highway, then presumably you live on a highway.
> To me, “living near a highway” sounds a lot like a euphemism for “living in the middle of nowhere”
I would have thought the opposite. Essentially no-one lives directly adjacent to a rural highway in the sense of overlooking it in the UK, even say the M25 doesn't have flats lining it, generally arterial roads have setbacks so you might be able to hear the cars etc but you've probably got a buffer zone measured in the tens of meters.
The actual roads I'd be thinking of are things like the A406 (North Circular Road), A40, A4, etc, which do have houses and flats immediately next to it. The sort of 'inner-city' 40-50mph urban clearways. There are also a ton of 30mph roads which serve a similar purpose. Basically what one would call a 'main road' as opposed to a side street.
Example of a sort of middling neighbourhood: https://goo.gl/maps/o6oSRW84dx147TK48 (this bit of the A40 is either 40mph or 30mph but has an absolute ton of traffic almost all of the time).
> “living near a highway” sounds a lot like a euphemism for “living in the middle of nowhere”, since by definition all arterial roads connecting “somewhere” to “somewhere” through “nowhere” are highways.
The study uses a definition based on average vehicles per day that travel the road. I think you're interpreting "highway" like a road that connects two cities, which is one of the word's many meanings, but they are using a different definition.
By using a traffic-based definition, this study is roughly counting the number of (running) cars that you're near.
Also, with their definition, people in urban or rural areas can be either near or not near a highway. If you live in the middle of a city but you're removed from high-traffic roads by neighborhood streets with low traffic, you're not near a highway.
> To me, “living near a highway” sounds a lot like a euphemism for “living in the middle of nowhere”
In more (sub)urban settings, I read it as "poor." But either way, it does seem hard to properly control for, and my gut tells me socioeconomic factors drive this more than pollution.
Or just that being close to a highway is often unpleasant, so those who can afford more pleasant parts of town have already done so. Surely they tried to control for wealth but it's easy to do so imperfectly. (Haven't read the paper, though!)
There are multiple major highways in urban greater Vancouver. The Trans Canada is the big one, and Oak street is essentially highway 99 (which becomes the I5)
Are residences near highways, perhaps farther from certain other things, like city centres? Such that a certain type of person (people with pre-existing [perhaps subclinical] mental issues of the type that might make them want to avoid people) would be drawn to live in these residences more than others?
To me, “living near a highway” sounds a lot like a euphemism for “living in the middle of nowhere”, since by definition all arterial roads connecting “somewhere” to “somewhere” through “nowhere” are highways. If you live somewhere isolated that’s accessible at all by road, and you don’t have the budget to build your own long stretch of lane out from the highway, then presumably you live on a highway.