Frequencies for first 10,000 rows of role_cod variable in drug2006q1 dataset :

   Code for |
     drug's |
   reported |
    role in |
      event |      Freq.     Percent        Cum.
------------+-----------------------------------
          C |      6,056       60.56       60.56
          I |         31        0.31       60.87
         PS |      2,230       22.30       83.17
         SS |      1,683       16.83      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 18 Dec 2015