Inverse white coat effect

You probably heard of this one: blood pressure is higher in the doctor's office than when measured outside. Something about worry and authority figures...

I seemed to have the opposite effect. Mine read lower at the doc's than at home. Was I reminded of my mother (a nurse) and comforted there?

Not exactly.

It was an artifact of furniture. The nurse always took my pressure on the right arm, since the chairs are at the left of the desks, and at home the right-handed me found it more convenient to take it on the left. It turns out the readings are not the same; the right is inconsistently lower. Not by enough to worry about (which would be consistently >10mm Hg on diastolic), but enough to confuse me over the years.

Try it yourself. It seems to be fairly common. (And if you repeat the measurement on the same side without waiting, the values are lower--apparently the arm takes a few minutes to recover.) Of course the highest values are the real ones. Unfortunately.