[DoctorTan]

The window period for HIV testing is a complex topic. The problem is you have people writing official guidelines that are intentionally over conservative. This is usually to serve an agenda of discouraging high risk behaviours and legally protecting their backsides. This unfortunately is not a true reflection of real world science and stats. Also unfortunately, while doctors want to give you advice based on real world science, our balls are held fast by the people who write these guidelines. Woe befalls he who goes against the guidelines. Mix this in with the fact that there are at least 6 different types of HIV tests out there with multiple companies making their own test kits each with its own performance characteristics and you get a huge mess of confusing numbers ranging from 10 days to 1 year. In Singapore, officially a HIV test is conclusive if conducted by a trained medical professional using a 3rd Generation ELISA test for HIV 1 and 2 antibodies conducted at 3 months from the date of possible infection.