Thanks, I don’t have a headboard. I’m in a bed with a queen mattress on a platform bed. I put the wedge under the mattress. My husband and I were going to buy a new bed or beds ,but decided to see if elevation helps. Actually do think my elevation is more or less correct, but will buy a wedge meant for this on Monday .. (I see many on this list find they may “ slide down” - I sometimes do but I don’t THAT much) .. I never had night time reflux until this endoflip test. I wonder if some type of irritation from endoflip and will get better as time passes. .