How reliable is the American Religious Identification Survey?

[Batfink]

This isn’t really ‘news’ since it was published in 2008, but it is kind of medis and it didn’t fit anywhere else.

I was doing some research and came across the above mentioned ARIS: commons.trincoll.edu/aris/files/2011/08/ARIS_Report_2008.pdf

Not being American, I’ve never heard of it before, so I wondered whether people who had knew of its trustworthiness/general reputation.

I was slightly concerned to read that, among their definitions of a Catholic, they include people who self-identify as Catholic, presumably High-Church Anglicans as well as various other groups (maybe the Old Catholic Church, people who are thinking about joining RCIA, well, anyone really).

Also, they don’t mention Orthodox or any Eastern Churches (except to say that Eastern Rite Catholics are Catholic, which is big of them ), so I guess they’re included in ‘Mainline Christian’ or ‘Generic Christian’, which is not untrue but quite misleading.

I haven’t even read down as far as the other religions bit as I was having serious doubts about the scholarship.

Could anyone enlighten/reassure/confirm my suspicions?

Thanks