I have z-scores on BMI, I created them using the egen function zanthro() and they look like the below. As they are negative and positive (i.e. above and below 0) I was advised to transform them into a percentile for a simpler outcome variable in my analysis.

After doing some reading online I made use of the following command:

Code:
gen ba_Pwho1=normal(ba_who1)*100
(I multiplied by 100 to have things that looked like actual percentages, i.e. 85 vs 0.85).

My problem is that I really am not quite sure what this command does, I searched the help file in Stata and read the manual reference here: https://www.stata.com/manuals13/m-5normal.pdf, but I think that the function is so simple that it hasn't been explained in any great detail anywhere.

What I really want to know is, what is it doing to my z-scores? And how is it getting them all to be a positive percentage when before they were between -5 and +5?

Sorry for how basic a question this is but I don't want to mindlessly use a command I don't understand!

Thank you,

John


Code:
* Example generated by -dataex-. To install: ssc install dataex
clear
input float(O_babybmi_y0 ba_who1 ba_Pwho1)
 18.77551  1.0723447  85.82174
15.704894 -1.1970643 11.564075
17.034914 -.05722509   47.7183
17.873068   .4596057  67.71004
16.252739   -.680801  24.79987
 16.88889 -.20153786   42.0139
 19.73684  1.7031987  95.57346
 18.17761   .6334454  73.67786
17.472918  .25589836  60.09853
 19.64826   1.669161  95.24573
17.068645  -.0882321  46.48461
17.548388  .27083287  60.67402
18.170197    .659906 74.534294
21.359306  2.6235385   99.5649
16.816326  -.2175362  41.38953
18.367348    .790473  78.53742
15.860992  -.7132174  23.78556
 18.64918  1.1620015  87.73826
 16.66336 -.05200634  47.92618
        .          .         .
13.779842 -2.2729416  1.151485
15.472163  -.8600693 19.487543
 19.48157   1.705609  95.59595
17.357668   .4610227  67.76088
19.146004  1.4186926  92.20057
18.488888  1.0840575  86.08303
 18.77393   1.251105  89.45519
 17.65306  .57482743   71.7296
 23.28903  3.5338855  99.97952
 15.51695  -.9075486 18.205837
 18.07372    .852188  80.29451
18.845469  1.2925274  90.19127
        .          .         .
 12.94802  -2.990553 .13923655
16.891891  .13761866  55.47291
15.339663  -.9591771 16.873476
14.965987  -1.370883   8.52057
16.308489  -.6378189 26.179577
19.946667   1.809395  96.48051
 21.20845    2.56019  99.47692
 21.42432   2.640918  99.58659
16.984457 -.13159405  44.76527
 16.34349  -.6283205   26.4897
 22.18549    3.05731  99.88834
16.836735 -.25763813  39.83431
18.626734   .9948871  84.01044
18.402777   .7822757  78.29737
19.242214  1.3658224  91.40027
18.197378   .7133805  76.21948
17.955557   .5509483  70.91654
17.013887 -.16068186   43.6172
18.074793   .6313974  73.61096
 17.48059   .2419935  59.56074
 21.82107   2.818688   99.7589
17.409164  .17308155  56.87063
    18.75  1.0741308  85.86179
17.315296  .08866534   53.5326
        .          .         .
18.547909   .9625777  83.21203
 17.49392  .13001922  55.17244
17.213558   .0339887  51.35569
16.824226 -.24915966  40.16187
 18.75696  1.0785846  85.96135
16.344046  -.6105064  27.07632
 16.88889  -.1831202  42.73518
21.307964   2.544808  99.45331
 19.40547  1.5028424  93.35602
20.818113    2.32715  99.00214
16.964027  -.1969443  42.19356
 17.83241   .5051757  69.32823
19.733515   1.602662  94.54954
19.285715  1.3927017   91.8145
19.733334  1.6826403  95.37776
 15.91435  -.9281714 17.665934
 20.68375    2.25198  98.78382
 20.04082   1.864769  96.88931
 20.00375  1.8430102  96.73363
19.675924   1.666703  95.22132
 19.95636   1.688411  95.43338
  18.1916    .709533  76.10031
 20.63265    2.17098  98.50336
        .          .         .
15.822222 -1.0193982 15.400698
 24.89796    4.28968  99.99911
19.555555  1.6132612  94.66561
18.436762    .871398  80.82316
19.907406  1.7683803  96.15013
17.622288   .3223055  62.63894
18.802776  1.0897518  86.20888
20.710176  2.2488105  98.77377
15.296593   -1.44964  7.357946
17.456856   .2847826  61.20947
18.151161   .7206602  76.44407
18.524931   .9669998  83.32279
 17.88347  .50196916  69.21554
 15.47325 -1.3843465  8.312619
17.839293    .453756  67.49978
 21.02623   2.424507  99.23354
 18.98659  1.1890045  88.27811
17.203577 .064608045   52.5757
end