The NBME just released the updated 2015 sample questions this past month, and there are no new questions in this iteration (at least in the downloadable pdf version). In fact, six questions have been removed (two from each section), which was done to reflect the decrease in total Step 1 test items starting May 11 from 322 to 308.
I’ve made a note of which questions were removed from the 2014-15 set. Therefore, at this time, my explanations for the 2014-15 set are still current. The question order is the same, but the numbering is off a bit.
If an updated set with new questions is eventually released, the explanations will appear below as they have in prior years.
#20 and #29 from 2014-15 were removed.
#74 and #85 from 2014-15 were removed.
#98 and #130 from 2014-15 were removed.
Again, the still current 2014-15 explanations can be found here.