library(ggplot2)
## Warning: package 'ggplot2' was built under R version 4.3.3
library(ggpubr)
## Warning: package 'ggpubr' was built under R version 4.3.2
library(carData)
## Warning: package 'carData' was built under R version 4.3.2
library(survival)
## Warning: package 'survival' was built under R version 4.3.3
library(car)
## Warning: package 'car' was built under R version 4.3.3
hmohiv<-read.table("https://stats.idre.ucla.edu/stat/r/examples/asa/hmohiv.csv", sep=",", header = TRUE)
s_obj<-Surv(hmohiv$time,hmohiv$censor)
hmohiv
##      ID time age drug censor     entdate     enddate
## 1     1    5  46    0      1  5/15/1990  10/14/1990 
## 2     2    6  35    1      0  9/19/1989   3/20/1990 
## 3     3    8  30    1      1  4/21/1991  12/20/1991 
## 4     4    3  30    1      1   1/3/1991    4/4/1991 
## 5     5   22  36    0      1  9/18/1989   7/19/1991 
## 6     6    1  32    1      0  3/18/1991   4/17/1991 
## 7     7    7  36    1      1 11/11/1989   6/11/1990 
## 8     8    9  31    1      1 11/25/1989   8/25/1990 
## 9     9    3  48    0      1  2/11/1991   5/13/1991 
## 10   10   12  47    0      1  8/11/1989   8/11/1990 
## 11   11    2  28    1      0  4/11/1990   6/10/1990 
## 12   12   12  34    0      1  5/11/1991   5/10/1992 
## 13   13    1  44    1      1  1/17/1989   2/16/1989 
## 14   14   15  32    1      1  2/16/1991   5/17/1992 
## 15   15   34  36    0      1   4/9/1991    2/6/1994 
## 16   16    1  36    0      1   3/9/1991    4/8/1991 
## 17   17    4  54    0      1   8/3/1990   12/2/1990 
## 18   18   19  35    0      0  6/10/1990    1/8/1992 
## 19   19    3  44    1      0  6/12/1991   9/11/1991 
## 20   20    2  38    0      1   1/7/1991    3/8/1991 
## 21   21    2  40    0      0  8/29/1989  10/28/1989 
## 22   22    6  34    1      1  5/29/1989  11/27/1989 
## 23   23   60  25    0      0 11/16/1990  11/14/1995 
## 24   24   11  32    0      1   5/9/1990    4/8/1991 
## 25   25    2  42    1      0  9/10/1991   11/9/1991 
## 26   26    5  47    0      1 12/26/1991   5/26/1992 
## 27   27    4  30    0      0  5/29/1991   9/27/1991 
## 28   28    1  47    1      1   5/1/1990   5/31/1990 
## 29   29   13  41    0      1  3/24/1991   4/22/1992 
## 30   30    3  40    1      1  7/18/1989  10/17/1989 
## 31   31    2  43    0      1  9/16/1990  11/15/1990 
## 32   32    1  41    0      1  6/22/1989   7/22/1989 
## 33   33   30  30    0      1  4/27/1990  10/25/1992 
## 34   34    7  37    0      1  5/16/1990  12/14/1990 
## 35   35    4  42    1      1  2/19/1989   6/20/1989 
## 36   36    8  31    1      1  2/17/1990  10/18/1990 
## 37   37    5  39    1      1   8/6/1991    1/5/1992 
## 38   38   10  32    0      1  8/10/1989   6/10/1990 
## 39   39    2  51    0      1 12/27/1990   2/25/1991 
## 40   40    9  36    0      1  4/26/1989   1/24/1990 
## 41   41   36  43    0      1  12/4/1990   12/3/1993 
## 42   42    3  39    0      1  4/28/1991   7/28/1991 
## 43   43    9  33    0      1   7/9/1991    4/7/1992 
## 44   44    3  45    1      1 12/31/1989    4/1/1990 
## 45   45   35  33    0      1 12/20/1989  11/18/1992 
## 46   46    8  28    0      1  6/22/1991   2/20/1992 
## 47   47   11  31    0      1  4/11/1990   3/11/1991 
## 48   48   56  20    1      0  5/22/1990   1/19/1995 
## 49   49    2  44    0      0 11/11/1991   1/10/1992 
## 50   50    3  39    1      1  1/18/1991   4/19/1991 
## 51   51   15  33    0      1 11/11/1989   2/10/1991 
## 52   52    1  31    0      1  10/1/1990  10/31/1990 
## 53   53   10  33    0      1  3/20/1990   1/18/1991 
## 54   54    1  50    1      1  7/30/1990   8/29/1990 
## 55   55    7  36    1      1  7/17/1989   2/14/1990 
## 56   56    3  30    1      1 11/10/1990    2/9/1991 
## 57   57    3  42    1      1   3/5/1989    6/4/1989 
## 58   58    2  32    1      1   3/2/1991    5/1/1991 
## 59   59   32  34    0      1  9/11/1989   5/11/1992 
## 60   60    3  38    1      1  9/12/1989  12/12/1989 
## 61   61   10  33    0      0   4/8/1990    2/6/1991 
## 62   62   11  39    1      1  4/20/1989   3/20/1990 
## 63   63    3  39    1      1  1/31/1991    5/2/1991 
## 64   64    7  33    1      1  9/15/1989   4/15/1990 
## 65   65    5  34    1      1  12/7/1991    5/7/1992 
## 66   66   31  34    0      1   3/4/1990   10/1/1992 
## 67   67    5  46    1      1  4/20/1989   9/19/1989 
## 68   68   58  22    0      1  6/16/1989   4/15/1994 
## 69   69    1  44    1      1  10/1/1990  10/31/1990 
## 70   70    3  37    0      0   2/1/1991    5/3/1991 
## 71   71   43  25    0      1  5/13/1989  12/10/1992 
## 72   72    1  38    0      1   8/9/1990    9/8/1990 
## 73   73    6  32    0      1 12/18/1991   6/17/1992 
## 74   74   53  34    0      1  8/23/1990   1/21/1995 
## 75   75   14  29    0      1  1/19/1991   3/19/1992 
## 76   76    4  36    1      1  8/26/1991  12/25/1991 
## 77   77   54  21    0      1  5/16/1991  11/13/1995 
## 78   78    1  26    1      1  3/20/1989   4/19/1989 
## 79   79    1  32    1      1  10/5/1991   11/4/1991 
## 80   80    8  42    0      1  5/21/1991   1/19/1992 
## 81   81    5  40    1      1  6/10/1991   11/9/1991 
## 82   82    1  37    1      1  8/31/1989   9/30/1989 
## 83   83    1  47    0      1 12/28/1991   1/27/1992 
## 84   84    2  32    1      1  9/29/1990  11/28/1990 
## 85   85    7  41    1      0 11/20/1991   6/19/1992 
## 86   86    1  46    1      0   7/2/1989    8/1/1989 
## 87   87   10  26    1      1 10/11/1991   8/10/1992 
## 88   88   24  30    0      0 10/11/1990  10/10/1992 
## 89   89    7  32    1      1  12/5/1990    7/5/1991 
## 90   90   12  31    1      0   9/8/1989    9/8/1990 
## 91   91    4  35    0      1  4/10/1990    8/9/1990 
## 92   92   57  36    0      1 12/11/1990    9/9/1995 
## 93   93    1  41    1      1 12/15/1990   1/14/1991 
## 94   94   12  36    1      0  1/13/1989   1/13/1990 
## 95   95    7  35    1      1  8/22/1991   3/21/1992 
## 96   96    1  34    1      1   8/2/1991    9/1/1991 
## 97   97    5  28    0      1  5/22/1991  10/21/1991 
## 98   98   60  29    0      0   4/2/1990    4/1/1995 
## 99   99    2  35    1      0   5/1/1991   6/30/1991 
## 100 100    1  34    1      1  5/11/1989   6/10/1989
  1. Ubah variabel ‘age’ menjadi variabel kategorik sebagai berikut, 20-29 : cage_1 30-39 : cage_2 40-49 : cage_3 50-54 : cage_4
hmohiv$cage<-recode(hmohiv$age, "20:29='cage_1'; 30:39='cage_2'; 40:49='cage_3';50:54='cage_4'", as.factor = TRUE)
hmohiv
##      ID time age drug censor     entdate     enddate   cage
## 1     1    5  46    0      1  5/15/1990  10/14/1990  cage_3
## 2     2    6  35    1      0  9/19/1989   3/20/1990  cage_2
## 3     3    8  30    1      1  4/21/1991  12/20/1991  cage_2
## 4     4    3  30    1      1   1/3/1991    4/4/1991  cage_2
## 5     5   22  36    0      1  9/18/1989   7/19/1991  cage_2
## 6     6    1  32    1      0  3/18/1991   4/17/1991  cage_2
## 7     7    7  36    1      1 11/11/1989   6/11/1990  cage_2
## 8     8    9  31    1      1 11/25/1989   8/25/1990  cage_2
## 9     9    3  48    0      1  2/11/1991   5/13/1991  cage_3
## 10   10   12  47    0      1  8/11/1989   8/11/1990  cage_3
## 11   11    2  28    1      0  4/11/1990   6/10/1990  cage_1
## 12   12   12  34    0      1  5/11/1991   5/10/1992  cage_2
## 13   13    1  44    1      1  1/17/1989   2/16/1989  cage_3
## 14   14   15  32    1      1  2/16/1991   5/17/1992  cage_2
## 15   15   34  36    0      1   4/9/1991    2/6/1994  cage_2
## 16   16    1  36    0      1   3/9/1991    4/8/1991  cage_2
## 17   17    4  54    0      1   8/3/1990   12/2/1990  cage_4
## 18   18   19  35    0      0  6/10/1990    1/8/1992  cage_2
## 19   19    3  44    1      0  6/12/1991   9/11/1991  cage_3
## 20   20    2  38    0      1   1/7/1991    3/8/1991  cage_2
## 21   21    2  40    0      0  8/29/1989  10/28/1989  cage_3
## 22   22    6  34    1      1  5/29/1989  11/27/1989  cage_2
## 23   23   60  25    0      0 11/16/1990  11/14/1995  cage_1
## 24   24   11  32    0      1   5/9/1990    4/8/1991  cage_2
## 25   25    2  42    1      0  9/10/1991   11/9/1991  cage_3
## 26   26    5  47    0      1 12/26/1991   5/26/1992  cage_3
## 27   27    4  30    0      0  5/29/1991   9/27/1991  cage_2
## 28   28    1  47    1      1   5/1/1990   5/31/1990  cage_3
## 29   29   13  41    0      1  3/24/1991   4/22/1992  cage_3
## 30   30    3  40    1      1  7/18/1989  10/17/1989  cage_3
## 31   31    2  43    0      1  9/16/1990  11/15/1990  cage_3
## 32   32    1  41    0      1  6/22/1989   7/22/1989  cage_3
## 33   33   30  30    0      1  4/27/1990  10/25/1992  cage_2
## 34   34    7  37    0      1  5/16/1990  12/14/1990  cage_2
## 35   35    4  42    1      1  2/19/1989   6/20/1989  cage_3
## 36   36    8  31    1      1  2/17/1990  10/18/1990  cage_2
## 37   37    5  39    1      1   8/6/1991    1/5/1992  cage_2
## 38   38   10  32    0      1  8/10/1989   6/10/1990  cage_2
## 39   39    2  51    0      1 12/27/1990   2/25/1991  cage_4
## 40   40    9  36    0      1  4/26/1989   1/24/1990  cage_2
## 41   41   36  43    0      1  12/4/1990   12/3/1993  cage_3
## 42   42    3  39    0      1  4/28/1991   7/28/1991  cage_2
## 43   43    9  33    0      1   7/9/1991    4/7/1992  cage_2
## 44   44    3  45    1      1 12/31/1989    4/1/1990  cage_3
## 45   45   35  33    0      1 12/20/1989  11/18/1992  cage_2
## 46   46    8  28    0      1  6/22/1991   2/20/1992  cage_1
## 47   47   11  31    0      1  4/11/1990   3/11/1991  cage_2
## 48   48   56  20    1      0  5/22/1990   1/19/1995  cage_1
## 49   49    2  44    0      0 11/11/1991   1/10/1992  cage_3
## 50   50    3  39    1      1  1/18/1991   4/19/1991  cage_2
## 51   51   15  33    0      1 11/11/1989   2/10/1991  cage_2
## 52   52    1  31    0      1  10/1/1990  10/31/1990  cage_2
## 53   53   10  33    0      1  3/20/1990   1/18/1991  cage_2
## 54   54    1  50    1      1  7/30/1990   8/29/1990  cage_4
## 55   55    7  36    1      1  7/17/1989   2/14/1990  cage_2
## 56   56    3  30    1      1 11/10/1990    2/9/1991  cage_2
## 57   57    3  42    1      1   3/5/1989    6/4/1989  cage_3
## 58   58    2  32    1      1   3/2/1991    5/1/1991  cage_2
## 59   59   32  34    0      1  9/11/1989   5/11/1992  cage_2
## 60   60    3  38    1      1  9/12/1989  12/12/1989  cage_2
## 61   61   10  33    0      0   4/8/1990    2/6/1991  cage_2
## 62   62   11  39    1      1  4/20/1989   3/20/1990  cage_2
## 63   63    3  39    1      1  1/31/1991    5/2/1991  cage_2
## 64   64    7  33    1      1  9/15/1989   4/15/1990  cage_2
## 65   65    5  34    1      1  12/7/1991    5/7/1992  cage_2
## 66   66   31  34    0      1   3/4/1990   10/1/1992  cage_2
## 67   67    5  46    1      1  4/20/1989   9/19/1989  cage_3
## 68   68   58  22    0      1  6/16/1989   4/15/1994  cage_1
## 69   69    1  44    1      1  10/1/1990  10/31/1990  cage_3
## 70   70    3  37    0      0   2/1/1991    5/3/1991  cage_2
## 71   71   43  25    0      1  5/13/1989  12/10/1992  cage_1
## 72   72    1  38    0      1   8/9/1990    9/8/1990  cage_2
## 73   73    6  32    0      1 12/18/1991   6/17/1992  cage_2
## 74   74   53  34    0      1  8/23/1990   1/21/1995  cage_2
## 75   75   14  29    0      1  1/19/1991   3/19/1992  cage_1
## 76   76    4  36    1      1  8/26/1991  12/25/1991  cage_2
## 77   77   54  21    0      1  5/16/1991  11/13/1995  cage_1
## 78   78    1  26    1      1  3/20/1989   4/19/1989  cage_1
## 79   79    1  32    1      1  10/5/1991   11/4/1991  cage_2
## 80   80    8  42    0      1  5/21/1991   1/19/1992  cage_3
## 81   81    5  40    1      1  6/10/1991   11/9/1991  cage_3
## 82   82    1  37    1      1  8/31/1989   9/30/1989  cage_2
## 83   83    1  47    0      1 12/28/1991   1/27/1992  cage_3
## 84   84    2  32    1      1  9/29/1990  11/28/1990  cage_2
## 85   85    7  41    1      0 11/20/1991   6/19/1992  cage_3
## 86   86    1  46    1      0   7/2/1989    8/1/1989  cage_3
## 87   87   10  26    1      1 10/11/1991   8/10/1992  cage_1
## 88   88   24  30    0      0 10/11/1990  10/10/1992  cage_2
## 89   89    7  32    1      1  12/5/1990    7/5/1991  cage_2
## 90   90   12  31    1      0   9/8/1989    9/8/1990  cage_2
## 91   91    4  35    0      1  4/10/1990    8/9/1990  cage_2
## 92   92   57  36    0      1 12/11/1990    9/9/1995  cage_2
## 93   93    1  41    1      1 12/15/1990   1/14/1991  cage_3
## 94   94   12  36    1      0  1/13/1989   1/13/1990  cage_2
## 95   95    7  35    1      1  8/22/1991   3/21/1992  cage_2
## 96   96    1  34    1      1   8/2/1991    9/1/1991  cage_2
## 97   97    5  28    0      1  5/22/1991  10/21/1991  cage_1
## 98   98   60  29    0      0   4/2/1990    4/1/1995  cage_1
## 99   99    2  35    1      0   5/1/1991   6/30/1991  cage_2
## 100 100    1  34    1      1  5/11/1989   6/10/1989  cage_2
cage.coxph <- coxph( s_obj ~ hmohiv$cage, data = hmohiv, method="breslow")
summary(cage.coxph)
## Call:
## coxph(formula = s_obj ~ hmohiv$cage, data = hmohiv, method = "breslow")
## 
##   n= 100, number of events= 80 
## 
##                      coef exp(coef) se(coef)     z Pr(>|z|)    
## hmohiv$cagecage_2  1.2552    3.5086   0.4315 2.909  0.00362 ** 
## hmohiv$cagecage_3  1.7974    6.0340   0.4762 3.774  0.00016 ***
## hmohiv$cagecage_4  2.7635   15.8552   0.7350 3.760  0.00017 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
##                   exp(coef) exp(-coef) lower .95 upper .95
## hmohiv$cagecage_2     3.509    0.28501     1.506     8.174
## hmohiv$cagecage_3     6.034    0.16573     2.373    15.345
## hmohiv$cagecage_4    15.855    0.06307     3.755    66.954
## 
## Concordance= 0.63  (se = 0.033 )
## Likelihood ratio test= 21.29  on 3 df,   p=9e-05
## Wald test            = 19.28  on 3 df,   p=2e-04
## Score (logrank) test = 21.96  on 3 df,   p=7e-05
  1. Buat model Cox PH dengan variabel penjelas drug (ref:drug=1) dan cage (ref: cage_3)
cdrug <- as.factor(hmohiv$drug)  
cdrug <- relevel(cdrug, ref = "1")
hmohiv$cage <- relevel(hmohiv$cage, ref = "cage_3")
cox_model <- coxph(s_obj ~ cage + drug , data = hmohiv, method = "breslow")
summary(cox_model)
## Call:
## coxph(formula = s_obj ~ cage + drug, data = hmohiv, method = "breslow")
## 
##   n= 100, number of events= 80 
## 
##               coef exp(coef) se(coef)      z Pr(>|z|)    
## cagecage_1 -1.8771    0.1530   0.4879 -3.847 0.000119 ***
## cagecage_2 -0.5991    0.5493   0.2750 -2.178 0.029385 *  
## cagecage_4  1.2308    3.4239   0.6354  1.937 0.052741 .  
## drug        0.8711    2.3895   0.2532  3.440 0.000581 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
##            exp(coef) exp(-coef) lower .95 upper .95
## cagecage_1    0.1530     6.5345   0.05882    0.3982
## cagecage_2    0.5493     1.8204   0.32044    0.9417
## cagecage_4    3.4239     0.2921   0.98554   11.8954
## drug          2.3895     0.4185   1.45475    3.9247
## 
## Concordance= 0.685  (se = 0.034 )
## Likelihood ratio test= 33.11  on 4 df,   p=1e-06
## Wald test            = 29.43  on 4 df,   p=6e-06
## Score (logrank) test = 32.93  on 4 df,   p=1e-06
  1. Interpretasikan hasilnya!