Do nsaids cause false positive fobt results? why are there so many controversial articles reaching completely opposite conclusions? are there any convincing meta study or general consensus on the issue?

In some people NSAIDS cause blood in the GI tract causing positive FOBT. All tests have false positive and false negative tests un- predictably in individuals. so no study however extensive or mega will answer this question conclusively- and there is none.

If one takes NSAID one is more likely to bleed and therefore more likely to have a positive Fecal Occult Blood Test (FOBT). Medications such as antiplatelet agents (eg, low-dose aspirin), nonsteroidal anti-inflammatory drugs, and oral anticoagulants can result in a false-positive FOBT owing to insignificant gastrointestinal losses.