Not to confuse matters, sensitivity may be measured using dB (1W/1M), dB(2.83V/1M) (and for the really lazy, just dB, move right along if you see that).
They are different. I understand that there is about a 3 dB difference between the watt and the volt measurements, all other things being equal. Watt higher? Happy to be corrected by an EE - ohms also come into play.
Read and weep right through if ya dare.