When researching cases, you need to determine two key things about a case:
1. Case History: has the case been appealed to a higher court, potentially all the way to the Supreme Court of Canada? If it has, the initial and/or subsequent decisions may have been changed, e.g. reversed, by the higher courts;
2. Case Consideration/Treatment: has the case been considered by later cases? If it has, the consideration may be positive or negative (also called judicial consideration/treatment).
As case history and consideration can both affect the precedent value of a case, information on this is made readily available in online case law databases, as part of the case report itself, or by using the database's "cite" feature, e.g. Quicklaw's QuickCite and Westlaw's KeyCite. Various symbols are used in the case report to indicate the history and consideration applying to a case; consult the User Guide or online help for an explanation of the symbols.