R 倾向匹配不匹配

我试图将对照组和我的疾病对应组进行匹配（下面是名为

mydata

    AGE SEX HXCHF HXCOPD  CASEID Disease
1    44   1     0      0 2902568     1
2    61   1     0      0 3022106     1
3    31   0     0      0 8390810     1
4    49   1     0      0 1821150     1
5    48   1     0      0 1942796     1
6    25   1     0      0 1944197     1
7    61   0     0      0 2048336     1
8    51   1     0      0 2068689     1
9    30   0     0      0 2189285     0
10   31   1     0      0 2307730     0

在匹配之前，这里是数据的样子。你会注意到有776个疾病病例和750638个非疾病病例

     Stratified by Disease
                     0              1             SMD   
  n                  750638           776               
  AGE (mean (SD))     56.19 (15.54) 50.72 (14.32)  0.366
  SEX (mean (SD))      0.66 (0.47)   0.48 (0.50)   0.359
  HXCHF (mean (SD))    0.01 (0.08)   0.00 (0.05)   0.054
  HXCOPD (mean (SD))   0.04 (0.20)   0.03 (0.17)   0.052

我用我想要匹配的变量运行倾向模型

        library(Matching)

        xvars <- c("AGE", "SEX", "HXCHF", "HXCOPD")
       
        greedymatch <- Match(Tr = Disease, M = 1, X = mydata[xvars])
   
        matched <- mydata[unlist(greedymatch[c("index.treated", "index.control")]),]

库（匹配）
xvars自行解决

向代码中添加
replace=FALSE

 greedymatch <- Match(Tr = Disease, M = 1, X = mydata[xvars], replace = FALSE)

greedymatch
 greedymatch <- Match(Tr = Disease, M = 1, X = mydata[xvars], replace = FALSE)