I am new to SUS questionnaire. I want to use five questions form SUS in my research. I am taking 3 even questions and 2 odd questions. Using questionnaire this way will it misinterpret my results. Can you please guide me how should i calculate my sus scores. Please help!!
As others have mentioned, picking a few questions at random from SUS isn't going to give you something that you can usefully use as a guideline.
If you're interested in specific factors then I'd take a look at Lewis & Sauro's paper on The Factor Structure of the System Usability Scale where they've done a bunch of research around that topic. That may give you some guidance on what questions you can drop depending on what you're interested in.
If you're after something shorter take a look at UMUX-LITE which is a two question test that corresponds pretty well to SUS.
You can't really. Full SUS scores depend upon all of the questions being asked. I guess you could use the standard calculations to give yourself a partial score...but that wouldn't really have much scientific worth at all. You need the full set for a proper SUS score calculation.