Frequencies for first 10,000 rows of prescr3 variable in nhamcsed2011 dataset :

        Prescription status code for |
                       medication #3 |      Freq.     Percent        Cum.
-------------------------------------+-----------------------------------
                   Prescription drug |      2,174       21.74       21.74
                Nonprescription drug |         63        0.63       22.37
                        Undetermined |         26        0.26       22.63
Prescription or Nonprescription drug |        732        7.32       29.95
                                   . |      7,005       70.05      100.00
-------------------------------------+-----------------------------------
                               Total |     10,000      100.00

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