Here at Whitespark we look at thousands of citation sites for our citation building service. Just as with links, not all citation sources are created equal, so it's super important that you are careful with where you submit. Some citations are going to help your rankings, and other citations could hurt your rankings.
To determine the quality of a citation source, we consider the following for every site we submit to:
1) Quality of link profile: Run a link report in MajesticSEO (I suggest Majestic because it has a deeper crawl and tends to report on more of the lower quality sites than OpenSiteExplorer). Does it look like a ton of exact match anchor text links from blog comments, forums, bookmarking sites, and cheap article directories? That's a concern and it indicates a site we will likely want to exclude.
2) Is it part of a network? There are some business listing networks out there that will create listings on dozens, or sometimes hundreds, of additional domains when you submit to one. This can create a massive link spike from low quality directory sites and actually hurt your rankings. You can test this by looking for a footprint from the site that will likely appear on all other sites (look in the footer). Search Google for that footprint (in quotes) and it may reveal other sites in their network. Now, to see if listings are distributed across all their network of sites, you can look at any listing on the site to get a phone number, then run a phone number search combined with the footprint like this: https://www.google.com/search?q=%22_footprint_here_%22+%22_phone_number_here_%22. If it looks like listings are being distributed across a ton of sites, avoid.
3) PageRank: a low PR could be a red flag. You can't immediately rule out a site based on this, but it does indicate that you should take a closer look at other metrics. There are cases where a site is new and might not have PR yet, so, as long as the other metrics check out ok, it could be good to submit to.
4) SEOMoz DA: Get this from Open Site Explorer. Ideally, DA will be 30 or greater for the sites we submit to. Again, a site with less than 30 for DA could still be ok to use as long as other metrics check out.
5) Number of Indexed Pages: Run a "site:www.domain.com" search in Google on the site. If the number of indexed pages is low (less than 100), then that could be a red flag, depending on the nature of the site.
6) Number of linking root domains: Get this metric from Open Site Explorer. For a local or hyper-niche site, a low number is ok. If it's a really high number, this could be a red flag that indicates some spammy link building practices. See #1 in this case.
7) Domain Age: You can get this from the Wayback Machine. Look up the site like this: http://web.archive.org/web/*/http://www.domain.com and look for text that says "going all the way back to _________". An older domain is generally better for a citation than a brand new domain, but not always. A new site with quality links is a better citation source than an old site with a super spammy link profile. Yes, I know you can get domain age from a whois search, but I prefer using the Wayback Machine because people can sit on domains for years before a site ever appears on it.
8) Check if they rank: Take a look at the homepage title tag. It will typically have the brand name in it. Run a search for that brand name. If the site doesn't even rank on the first page for their own brand name, that is a red flag.
9) Visual check: This is a tough one to use as a metric to assess quality because sites that were developed in 1996 and haven't had the design updated could still be awesome citation sources. You're looking for spam signals here, moreso than design quality. Does the site look like a big pile of spam? It probably is.
Really, there is no simple formula we can apply to determine citation source quality. You have to use your best judgement. A small local site that lists businesses in a small town might have low PR, low DA, hardly any links, very few indexed pages, and terrible design, but could still be an excellent citation source for a business in that community. In my opinion, the key metrics to check would be "quality of link profile" and "is it part of a network". If it fails either of those, avoid.
It's worth it to spend the time to weed out the good citations from the bad ones, because when Google sees your nice, clean citation profile they'll be all:
Do you have any additional checks that you consider when assessing citation quality? Leave a comment!