Contains data from psa_dre_v2.dta
  obs:        19,476                          DS Smith - prostate cancer
                                                screen: paired PSA & DRE cohort
                                                data
 vars:             4                          23 May 2007 15:50
 size:       155,808 (99.0% of memory free)   (_dta has notes)
-------------------------------------------------------------------------------
              storage  display     value
variable name   type   format      label      variable label
-------------------------------------------------------------------------------
race            byte   %9.0g       race       
psa             byte   %9.0g       yesno      serum PSA
dre             byte   %9.0g       yesno      DRE
d               byte   %9.0g       ynlbl    * Prostate cancer
                                            * indicated variables have notes
-------------------------------------------------------------------------------
Sorted by:  

**********************
value labels for variables with numeric codes:

ynlbl:
           0 no
           1 yes
yesno:
           0 neg
           1 pos
race:
           0 white
           1 black

*********************
notes:

_dta:
  1.  Data reference: Smith DS, Bullock AD, Catalona WJ. Racial differences in
      operating characteristics of prostate cancer screening tests. The Journal
      of Urology 158:1861-66. 1997.
  2.  5/23/07. psa_dre_v2.dta corrects an error in psa_dre.dta - the omission of
      three records for white subjects with neg DRE and neg PSA

d:
  1.  patients negative for both PSA and DRE were not biopsied, thus d is
      missing