Frequencies for first 10,000 rows of rx2v1c1 variable in nhamcsopd2006 dataset :

   for rx2, level 1 of multum |
             drug category #1 |      Freq.     Percent        Cum.
------------------------------+-----------------------------------
              Anti-infectives |        259        2.59        2.59
              Antineoplastics |         64        0.64        3.23
                  Biologicals |          7        0.07        3.30
        Cardiovascular agents |        528        5.28        8.58
Central nervous system agents |      1,053       10.53       19.11
        Coagulation modifiers |         55        0.55       19.66
      Gastrointestinal agents |        271        2.71       22.37
                     Hormones |        174        1.74       24.11
         Miscellaneous agents |        142        1.42       25.53
         Nutritional products |        263        2.63       28.16
           Respiratory agents |        437        4.37       32.53
               Topical agents |        250        2.50       35.03
        Alternative medicines |         20        0.20       35.23
     Psychotherapeutic agents |        380        3.80       39.03
         Immunological agents |        148        1.48       40.51
            Radiologic agents |          2        0.02       40.53
             Metabolic agents |        269        2.69       43.22
           Pharmaceutical aid |          4        0.04       43.26
                            . |      5,674       56.74      100.00
------------------------------+-----------------------------------
                        Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 28 Mar 2016