Hey caz.
The ovulation predictor kits (wee on a stick) are true as they are measuring the leutinizing hormone which triggers ovulation.
Why do you feel you are not getting clear results?
Remember, don't do it first thing in the morning. Do th at say 2pm and again at 8pm if you can afford that many sticks. And do it at the same times everyday. If they aren't coming up as dark or darker than the test line then keep going with them for a few more days. This is what happened to me. What I discovered was that I had a 30 day cycle and instead of ovulating day 14 or 15 like most books etc say, I was actually ov on days 20 and 21 so I would have missed by nearly 7 days.
My test results on the opks were 'nearly' positive so I kept using them and low and behold, 6 days later, a super strong dark line signaling the leutinizing hormone was being released and I would ov 24- 48 hrs after that.
Why aren't you getting clear results?????
Fingers crossed for this time though!!!