They check what you have submitted, but a final decision is not made until all of these checks are complete. Final decision is made based on the results of all checks needed - eligibility, admissibility, criminality, medical etc.
See here for a summary:
http://www.cic.gc.ca/english/immigrate/provincial/next_steps.asp
Decision on your application
CIC will make a decision on your application based on:
whether you meet the eligibility criteria for the program,
whether you have the funds to support yourself and your family when you arrive in Canada,
the results of your medical exam;
the information on your police certificate; and
any other information we have received.
If we need more information from you, we will let you know. We may also invite you to an interview.
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