Yes, it completely depends on what the disclaimer is about. For example, you can't disclaim liability for death or personal injury due to negligence. So some disclaimers will be unenforceable due to their subject matter (what they are trying to disclaim) and some will be unenforceable due to the manner in which they are presented (e.g. if you'd signed the NCT disclaimer after the actual test or if the terms are unconscionable small print etc.)
It will be difficult to research "disclaimers" per se but you should be able to find out info on the enforceability of certain disclaimers if you look up the subject disclaimed, if you see what I mean!
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