Hi,
I have been using sts list in survival function and I'm coming across a perplexing problem, and I'm at a standstill.
My survival function is the following:
stset ttpdac if fin_smoke!=4, failure (pdac) id(scrssn)
where pdac = pancreatic cancer, ttpdac = time to pdac or censoring
I am trying to get the cumulative failure rate at a certain time point (3 years) for a specific data cohort (set==1) by a prediction score (score_cat_3yr_5set1)
In this case, I type in
sts list if set==1, risktable (3) failure by (score_cat_3yr_5set1)
I should get more failure events the further out that I go. however, that is not the case when I type in 3 vs. 3.05 for the timepoint respectively. eg. at score bin 45, I get 3817 vs. 3791 failures respectively at timepoints 3 vs. 3.05. Why is that?
Additionally, I also created a variable pdac3 for the pdac cases within 3 years. However, that number doesn't correspond to the # of failures in the stslist table at timepoint 3. Why is that? see below for the tables.
. sts list if set==1 , risktable (3) failure by(score_cat_3yr_5set1)
Failure _d: pdac
Analysis time _t: ttpdac
ID variable: scrssn
Kaplan–Meier failure function
By variable: score_cat_3yr_5set1
At Net Failure Std.
Time risk Fail lost function error [95% conf. int.]
------------------------------------------------------------------------
0-
3 3054 0 3054 0.0000 . . .
5-
3 98480 9 9.8e+04 0.0000 0.0000 0.0000 0.0001
10-
3 232176 36 2.3e+05 0.0000 0.0000 0.0000 0.0001
15-
3 110596 18 1.1e+05 0.0001 0.0000 0.0000 0.0001
20-
3 34595 10 3.5e+04 0.0002 0.0001 0.0001 0.0003
25-
3 97212 66 9.7e+04 0.0001 0.0000 0.0001 0.0002
30-
3 160617 190 1.6e+05 0.0004 0.0000 0.0003 0.0005
35-
3 202740 545 2.0e+05 0.0005 0.0000 0.0005 0.0006
40-
3 339621 1411 3.4e+05 0.0012 0.0001 0.0011 0.0013
45-
3 694271 3817 6.9e+05 0.0022 0.0001 0.0021 0.0023
50-
3 1.0e+06 6389 1.0e+06 0.0038 0.0001 0.0037 0.0039
55-
3 515986 3763 5.1e+05 0.0060 0.0001 0.0058 0.0062
60-
3 130080 1073 1.3e+05 0.0095 0.0002 0.0091 0.0099
65-
3 20322 184 2.0e+04 0.0160 0.0007 0.0147 0.0173
70-
3 3797 55 3742 0.0330 0.0020 0.0293 0.0373
75-
3 1042 18 1024 0.0576 0.0050 0.0485 0.0683
80-
3 220 1 219 0.0807 0.0128 0.0591 0.1099
85-
3 33 0 33 0.0504 0.0263 0.0179 0.1376
90-
3 1 0 1 0.0000 . . .
95-
3 0 0 0 . . . .
------------------------------------------------------------------------
Notes: Survival-time summaries shown for specified times in (0, 20].
Net lost equals the number lost minus the number who entered.
. sts list if set==1 , risktable (3.05) failure by(score_cat_3yr_5set1)
Failure _d: pdac
Analysis time _t: ttpdac
ID variable: scrssn
Kaplan–Meier failure function
By variable: score_cat_3yr_5set1
At Net Failure Std.
Time risk Fail lost function error [95% conf. int.]
------------------------------------------------------------------------
0-
3.05 3011 0 3011 0.0000 . . .
5-
3.05 97353 9 9.7e+04 0.0000 0.0000 0.0000 0.0001
10-
3.05 229664 36 2.3e+05 0.0000 0.0000 0.0000 0.0001
15-
3.05 109492 18 1.1e+05 0.0001 0.0000 0.0000 0.0001
20-
3.05 34235 10 3.4e+04 0.0002 0.0001 0.0001 0.0003
25-
3.05 96343 65 9.6e+04 0.0001 0.0000 0.0001 0.0002
30-
3.05 159318 190 1.6e+05 0.0004 0.0000 0.0003 0.0005
35-
3.05 201244 545 2.0e+05 0.0005 0.0000 0.0005 0.0006
40-
3.05 337527 1402 3.4e+05 0.0012 0.0001 0.0011 0.0013
45-
3.05 689591 3791 6.9e+05 0.0022 0.0001 0.0021 0.0023
50-
3.05 993900 6329 9.9e+05 0.0038 0.0001 0.0037 0.0039
55-
3.05 510659 3718 5.1e+05 0.0061 0.0001 0.0059 0.0063
60-
3.05 128432 1053 1.3e+05 0.0096 0.0002 0.0092 0.0101
65-
3.05 20013 181 2.0e+04 0.0161 0.0007 0.0149 0.0174
70-
3.05 3727 53 3674 0.0335 0.0021 0.0297 0.0379
75-
3.05 1029 18 1011 0.0576 0.0050 0.0485 0.0683
80-
3.05 215 1 214 0.0807 0.0128 0.0591 0.1099
85-
3.05 32 0 32 0.0504 0.0263 0.0179 0.1376
90-
3.05 1 0 1 0.0000 . . .
95-
3.05 0 0 0 . . . .
------------------------------------------------------------------------
Notes: Survival-time summaries shown for specified times in (0, 20].
Net lost equals the number lost minus the number who entered.
. tab score_cat_3yr_5set1 pdac3 if fin_smoke!=4 & set==1
score_cat_ | PDAC3
3yr_5set1 | 0 1 | Total
-----------+----------------------+----------
0- | 5,360 0 | 5,360
5- | 152,567 3 | 152,570
10- | 333,124 10 | 333,134
15- | 151,169 8 | 151,177
20- | 51,129 7 | 51,136
25- | 137,394 17 | 137,411
30- | 217,311 71 | 217,382
35- | 273,027 134 | 273,161
40- | 446,769 475 | 447,244
45- | 934,904 1,867 | 936,771
50- | 1,485,134 4,863 | 1,489,997
55- | 896,969 4,350 | 901,319
60- | 292,727 2,038 | 294,765
65- | 60,098 656 | 60,754
70- | 12,502 286 | 12,788
75- | 3,258 140 | 3,398
80- | 792 44 | 836
85- | 150 4 | 154
90- | 11 0 | 11
95- | 5 0 | 5
-----------+----------------------+----------
Total | 5,454,400 14,973 | 5,469,373
Thanks,
Louise
I have been using sts list in survival function and I'm coming across a perplexing problem, and I'm at a standstill.
My survival function is the following:
stset ttpdac if fin_smoke!=4, failure (pdac) id(scrssn)
where pdac = pancreatic cancer, ttpdac = time to pdac or censoring
I am trying to get the cumulative failure rate at a certain time point (3 years) for a specific data cohort (set==1) by a prediction score (score_cat_3yr_5set1)
In this case, I type in
sts list if set==1, risktable (3) failure by (score_cat_3yr_5set1)
I should get more failure events the further out that I go. however, that is not the case when I type in 3 vs. 3.05 for the timepoint respectively. eg. at score bin 45, I get 3817 vs. 3791 failures respectively at timepoints 3 vs. 3.05. Why is that?
Additionally, I also created a variable pdac3 for the pdac cases within 3 years. However, that number doesn't correspond to the # of failures in the stslist table at timepoint 3. Why is that? see below for the tables.
. sts list if set==1 , risktable (3) failure by(score_cat_3yr_5set1)
Failure _d: pdac
Analysis time _t: ttpdac
ID variable: scrssn
Kaplan–Meier failure function
By variable: score_cat_3yr_5set1
At Net Failure Std.
Time risk Fail lost function error [95% conf. int.]
------------------------------------------------------------------------
0-
3 3054 0 3054 0.0000 . . .
5-
3 98480 9 9.8e+04 0.0000 0.0000 0.0000 0.0001
10-
3 232176 36 2.3e+05 0.0000 0.0000 0.0000 0.0001
15-
3 110596 18 1.1e+05 0.0001 0.0000 0.0000 0.0001
20-
3 34595 10 3.5e+04 0.0002 0.0001 0.0001 0.0003
25-
3 97212 66 9.7e+04 0.0001 0.0000 0.0001 0.0002
30-
3 160617 190 1.6e+05 0.0004 0.0000 0.0003 0.0005
35-
3 202740 545 2.0e+05 0.0005 0.0000 0.0005 0.0006
40-
3 339621 1411 3.4e+05 0.0012 0.0001 0.0011 0.0013
45-
3 694271 3817 6.9e+05 0.0022 0.0001 0.0021 0.0023
50-
3 1.0e+06 6389 1.0e+06 0.0038 0.0001 0.0037 0.0039
55-
3 515986 3763 5.1e+05 0.0060 0.0001 0.0058 0.0062
60-
3 130080 1073 1.3e+05 0.0095 0.0002 0.0091 0.0099
65-
3 20322 184 2.0e+04 0.0160 0.0007 0.0147 0.0173
70-
3 3797 55 3742 0.0330 0.0020 0.0293 0.0373
75-
3 1042 18 1024 0.0576 0.0050 0.0485 0.0683
80-
3 220 1 219 0.0807 0.0128 0.0591 0.1099
85-
3 33 0 33 0.0504 0.0263 0.0179 0.1376
90-
3 1 0 1 0.0000 . . .
95-
3 0 0 0 . . . .
------------------------------------------------------------------------
Notes: Survival-time summaries shown for specified times in (0, 20].
Net lost equals the number lost minus the number who entered.
. sts list if set==1 , risktable (3.05) failure by(score_cat_3yr_5set1)
Failure _d: pdac
Analysis time _t: ttpdac
ID variable: scrssn
Kaplan–Meier failure function
By variable: score_cat_3yr_5set1
At Net Failure Std.
Time risk Fail lost function error [95% conf. int.]
------------------------------------------------------------------------
0-
3.05 3011 0 3011 0.0000 . . .
5-
3.05 97353 9 9.7e+04 0.0000 0.0000 0.0000 0.0001
10-
3.05 229664 36 2.3e+05 0.0000 0.0000 0.0000 0.0001
15-
3.05 109492 18 1.1e+05 0.0001 0.0000 0.0000 0.0001
20-
3.05 34235 10 3.4e+04 0.0002 0.0001 0.0001 0.0003
25-
3.05 96343 65 9.6e+04 0.0001 0.0000 0.0001 0.0002
30-
3.05 159318 190 1.6e+05 0.0004 0.0000 0.0003 0.0005
35-
3.05 201244 545 2.0e+05 0.0005 0.0000 0.0005 0.0006
40-
3.05 337527 1402 3.4e+05 0.0012 0.0001 0.0011 0.0013
45-
3.05 689591 3791 6.9e+05 0.0022 0.0001 0.0021 0.0023
50-
3.05 993900 6329 9.9e+05 0.0038 0.0001 0.0037 0.0039
55-
3.05 510659 3718 5.1e+05 0.0061 0.0001 0.0059 0.0063
60-
3.05 128432 1053 1.3e+05 0.0096 0.0002 0.0092 0.0101
65-
3.05 20013 181 2.0e+04 0.0161 0.0007 0.0149 0.0174
70-
3.05 3727 53 3674 0.0335 0.0021 0.0297 0.0379
75-
3.05 1029 18 1011 0.0576 0.0050 0.0485 0.0683
80-
3.05 215 1 214 0.0807 0.0128 0.0591 0.1099
85-
3.05 32 0 32 0.0504 0.0263 0.0179 0.1376
90-
3.05 1 0 1 0.0000 . . .
95-
3.05 0 0 0 . . . .
------------------------------------------------------------------------
Notes: Survival-time summaries shown for specified times in (0, 20].
Net lost equals the number lost minus the number who entered.
. tab score_cat_3yr_5set1 pdac3 if fin_smoke!=4 & set==1
score_cat_ | PDAC3
3yr_5set1 | 0 1 | Total
-----------+----------------------+----------
0- | 5,360 0 | 5,360
5- | 152,567 3 | 152,570
10- | 333,124 10 | 333,134
15- | 151,169 8 | 151,177
20- | 51,129 7 | 51,136
25- | 137,394 17 | 137,411
30- | 217,311 71 | 217,382
35- | 273,027 134 | 273,161
40- | 446,769 475 | 447,244
45- | 934,904 1,867 | 936,771
50- | 1,485,134 4,863 | 1,489,997
55- | 896,969 4,350 | 901,319
60- | 292,727 2,038 | 294,765
65- | 60,098 656 | 60,754
70- | 12,502 286 | 12,788
75- | 3,258 140 | 3,398
80- | 792 44 | 836
85- | 150 4 | 154
90- | 11 0 | 11
95- | 5 0 | 5
-----------+----------------------+----------
Total | 5,454,400 14,973 | 5,469,373
Thanks,
Louise