Applications are normally run for credit using the 3 major credit companies: TransUnion, Experian, and Equifax. A company can get a combined report or sometimes they just run one. A decision to rent is then normally made by the owner, property management company, or both. The information is presented to the "decision maker" and it's not just based on that but also on references, job history, employment, etc.
That is "in general" and is the rule of thumb.