Documentation Example 5 for PROC PHREG

/****************************************************************/
/*          S A S   S A M P L E   L I B R A R Y                 */
/*                                                              */
/*    NAME: PHREX5                                              */
/*   TITLE: Documentation Example 5 for PROC PHREG              */
/* PRODUCT: STAT                                                */
/*  SYSTEM: ALL                                                 */
/*    KEYS: Conditional Logistic Regression, n:m Matched Sets   */
/*   PROCS: PHREG                                               */
/*    DATA: Krall et al (1975), "A Step-up Procedure for        */
/*          Selecting Variables Associated with Survival,"      */
/*          Biometrics, 31, pp 49-51                            */
/* SUPPORT: sasycs                                              */
/*     REF: SAS/STAT User's Guide, PROC PHREG Chapter           */
/*    MISC:                                                     */
/****************************************************************/

data LBW;
   input id Age Low LWT Smoke HT UI @@;
   Time=2-Low;
   datalines;
 25  16   1   130   0  0  0    143  16   0   110   0  0  0
166  16   0   112   0  0  0    167  16   0   135   1  0  0
189  16   0   135   1  0  0    206  16   0   170   0  0  0
216  16   0    95   0  0  0     37  17   1   130   1  0  1
 45  17   1   110   1  0  0     68  17   1   120   1  0  0
 71  17   1   120   0  0  0     83  17   1   142   0  1  0
 93  17   0   103   0  0  0    113  17   0   122   1  0  0
116  17   0   113   0  0  0    117  17   0   113   0  0  0
147  17   0   119   0  0  0    148  17   0   119   0  0  0
180  17   0   120   1  0  0     49  18   1   148   0  0  0
 50  18   1   110   1  0  0     89  18   0   107   1  0  1
100  18   0   100   1  0  0    101  18   0   100   1  0  0
132  18   0    90   1  0  1    133  18   0    90   1  0  1
168  18   0   229   0  0  0    205  18   0   120   1  0  0
208  18   0   120   0  0  0     23  19   1    91   1  0  1
 33  19   1   102   0  0  0     34  19   1   112   1  0  1
 85  19   0   182   0  0  1     96  19   0    95   0  0  0
 97  19   0   150   0  0  0    124  19   0   138   1  0  0
129  19   0   189   0  0  0    135  19   0   132   0  0  0
142  19   0   115   0  0  0    181  19   0   105   0  0  0
187  19   0   235   1  1  0    192  19   0   147   1  0  0
193  19   0   147   1  0  0    197  19   0   184   1  1  0
224  19   0   120   1  0  0     27  20   1   150   1  0  0
 31  20   1   125   0  0  1     40  20   1   120   1  0  0
 44  20   1    80   1  0  1     47  20   1   109   0  0  0
 51  20   1   121   1  0  1     60  20   1   122   1  0  0
 76  20   1   105   0  0  0     87  20   0   105   1  0  0
104  20   0   120   0  0  1    146  20   0   103   0  0  0
155  20   0   169   0  0  1    160  20   0   141   0  0  1
172  20   0   121   1  0  0    177  20   0   127   0  0  0
201  20   0   120   0  0  0    211  20   0   170   1  0  0
217  20   0   158   0  0  0     20  21   1   165   1  1  0
 28  21   1   200   0  0  1     30  21   1   103   0  0  0
 52  21   1   100   0  0  0     84  21   1   130   1  1  0
 88  21   0   108   1  0  1     91  21   0   124   0  0  0
128  21   0   185   1  0  0    131  21   0   160   0  0  0
144  21   0   110   1  0  1    186  21   0   134   0  0  0
219  21   0   115   0  0  0     42  22   1   130   1  0  1
 67  22   1   130   1  0  0     92  22   0   118   0  0  0
 98  22   0    95   0  1  0    137  22   0    85   1  0  0
138  22   0   120   0  1  0    140  22   0   130   1  0  0
161  22   0   158   0  0  0    162  22   0   112   1  0  0
174  22   0   131   0  0  0    184  22   0   125   0  0  0
204  22   0   169   0  0  0    220  22   0   129   0  0  0
 17  23   1    97   0  0  1     59  23   1   187   1  0  0
 63  23   1   120   0  0  0     69  23   1   110   1  0  0
 82  23   1    94   1  0  0    130  23   0   130   0  0  0
139  23   0   128   0  0  0    149  23   0   119   0  0  0
164  23   0   115   1  0  0    173  23   0   190   0  0  0
179  23   0   123   0  0  0    182  23   0   130   0  0  0
200  23   0   110   0  0  0     18  24   1   128   0  0  0
 19  24   1   132   0  1  0     29  24   1   155   1  0  0
 36  24   1   138   0  0  0     61  24   1   105   1  0  0
118  24   0    90   1  0  0    136  24   0   115   0  0  0
150  24   0   110   0  0  0    156  24   0   115   0  0  0
185  24   0   133   0  0  0    196  24   0   110   0  0  0
199  24   0   110   0  0  0    225  24   0   116   0  0  0
 13  25   1   105   0  1  0     15  25   1    85   0  0  1
 24  25   1   115   0  0  0     26  25   1    92   1  0  0
 32  25   1    89   0  0  0     46  25   1   105   0  0  0
103  25   0   118   1  0  0    111  25   0   120   0  0  1
120  25   0   155   0  0  0    121  25   0   125   0  0  0
169  25   0   140   0  0  0    188  25   0    95   1  0  1
202  25   0   241   0  1  0    215  25   0   120   0  0  0
221  25   0   130   0  0  0     35  26   1   117   1  0  0
 54  26   1    96   0  0  0     75  26   1   154   0  1  0
 77  26   1   190   1  0  0     95  26   0   113   1  0  0
115  26   0   168   1  0  0    154  26   0   133   1  0  0
218  26   0   160   0  0  0     16  27   1   150   0  0  0
 43  27   1   130   0  0  1    125  27   0   124   1  0  0
  4  28   1   120   1  0  1     79  28   1    95   1  0  0
105  28   0   120   1  0  0    109  28   0   120   0  0  0
112  28   0   167   0  0  0    151  28   0   140   0  0  0
159  28   0   250   1  0  0    212  28   0   134   0  0  0
214  28   0   130   0  0  0     10  29   1   130   0  0  1
 94  29   0   123   1  0  0    114  29   0   150   0  0  0
123  29   0   140   1  0  0    190  29   0   135   0  0  0
191  29   0   154   0  0  0    209  29   0   130   1  0  0
 65  30   1   142   1  0  0     99  30   0   107   0  0  1
141  30   0    95   1  0  0    145  30   0   153   0  0  0
176  30   0   110   0  0  0    195  30   0   137   0  0  0
203  30   0   112   0  0  0     56  31   1   102   1  0  0
107  31   0   100   0  0  1    126  31   0   215   1  0  0
163  31   0   150   1  0  0    222  31   0   120   0  0  0
 22  32   1   105   1  0  0    106  32   0   121   0  0  0
134  32   0   132   0  0  0    170  32   0   134   1  0  0
175  32   0   170   0  0  0    207  32   0   186   0  0  0
;

proc phreg data=LBW;
   model Time*Low(0)= LWT Smoke HT UI / ties=discrete;
   strata Age;
run;