I don't know what causes your sister's eye strain .Does she work on the computer all day ? Does she wear prescription glasses ? Why doesn't she want to see the doctor ? non prescription computer glasses do work for people who don't wear prescription glasses to ease the eye strain caused by long time working on the computer
Technically, it does. Computer glasses are made with anti-glare lenses that can protect the eyes from some glares and anti-reflective light from computer screen. So, From this point, it is good for eyes to wear computer glasses when you see computer screen. Even if you are perfect vision, you can wear non prescription computer glasses. So, you can have a try.