Frequencies for first 10,000 rows of prescr4 variable in nhamcsed2012 dataset :

        Prescription status code for |
                       medication #4 |      Freq.     Percent        Cum.
-------------------------------------+-----------------------------------
                   Prescription drug |      1,167       11.67       11.67
                Nonprescription drug |         31        0.31       11.98
                        Undetermined |         19        0.19       12.17
Prescription or Nonprescription drug |        583        5.83       18.00
                                   . |      8,200       82.00      100.00
-------------------------------------+-----------------------------------
                               Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 7 Nov 2016