 The chief concern with some of the rudiments was the placement of the accents, particularly on the double stroke roll.NARD followed their "Essential 13" rudiments with "The 13 Rudiments to Complete the 26 Standard American Drum Rudiments" in 1936, after polling their 246 members to see which rudiment should be included.These two sheets of rudiments, totaling just 26, are the only American rudiments recognized by NARD.