Frequencies for first 10,000 rows of prescr1 variable in nhamcsed2011 dataset :

        Prescription status code for |
                       medication #1 |      Freq.     Percent        Cum.
-------------------------------------+-----------------------------------
                   Prescription drug |      5,441       54.41       54.41
                Nonprescription drug |        130        1.30       55.71
                        Undetermined |         54        0.54       56.25
Prescription or Nonprescription drug |      2,245       22.45       78.70
                                   . |      2,130       21.30      100.00
-------------------------------------+-----------------------------------
                               Total |     10,000      100.00

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