Not sure that I'm using this correctly but I've tried in on numerous occasions, tried new batteries, etc and still doesn't seem to give accurate results. The forehead is always way off, placing by the ear seems to work the best, but still never gives the same reading twice, even if I try it seconds apart. Strange... I won't purchase again and won't recommend it to any of my family and friends. The reason I gave it 3 stars is because I am giving the company/device the benefit of the doubt that it's just a user error.