R 中的亚组分析

Question

我正在尝试使用 CPH 回归在 R 中进行亚组分析。我基本上有很多患有糖尿病 (Y/N) 和一定尿量 (>/<200ml). Looking to gauge the effect of this interaction on survival. I have managed to run the CPH for the diabetes group (across all urine amounts) using the below. I have also created subsets of the diabetes/urine amount combos (renamed the dataset for privacy).

# create new variable splitting above and below 200 ml urine amount
    xxxx$uacr200 <- ifelse(xxxx$uacr>=200,1,0)

# create a new categorical variable that combines diabetes status AND urine amount above and below 200
xxxx$dmuacrgr <- NA
xxxx$dmuacrgr[xxxx$uacr<200 & xxxx$diabfl=="N"] <- 1
xxxx$dmuacrgr[xxxx$uacr>=200 & xxxxl$diabfl=="N"] <- 2
xxxx$dmuacrgr[xxxx$uacr<200 & xxxx$diabfl=="Y"] <- 3
xxxx$dmuacrgr[xxxx$uacr>=200 & xxxx$diabfl=="Y"] <- 4

# create version of treatment variable that is coded as 1 and 0
xxxx$trt <- NA
xxxx$trt[xxxx$trt02pn==2] <- 1
xxxx$trt[xxxx$trt02pn==1] <- 0

xxxx_sub <- xxxx[,c("usubjid", "mageg1n","mgfrg1n","msexg1n","muacrg1n", "trt")]

#Diab subgroup analysis (across all urine amounts)

# fit cox model to estimate HRs in diabetes subgroups
cox_mod_diab <- coxph(Surv(aval, cnsr==0) ~ trt + trt*diabfl + diabfl +
                            mageg1n + mgfrg1n + msexg1n + muacrg1n + sitegr2n, 
                         data = zzzz, subset=(paramcd=="KDPDVASC"), ties="breslow")

    subg_cox_mod_diab <-            subgroupAnalysis(cox_mod_diab_int_KDPDVASC,zzzz[zzzz$paramcd=="KDPDVASC",],treatment="trt",
                                 subgroups=("diabfl"),confint.method="default") 

我现在只需要使用我上面创建的组合子集来找出对糖尿病的影响，在每个尿液量中......任何帮助都会救我！！

Answer 1

您将子组创建为

xxxx$dmuacrgr <- NA
xxxx$dmuacrgr[xxxx$uacr<200 & xxxx$diabfl=="N"] <- 1
xxxx$dmuacrgr[xxxx$uacr>=200 & xxxxl$diabfl=="N"] <- 2
xxxx$dmuacrgr[xxxx$uacr<200 & xxxx$diabfl=="Y"] <- 3
xxxx$dmuacrgr[xxxx$uacr>=200 & xxxx$diabfl=="Y"] <- 4

我建议按如下方式创建用于亚组分析的数据：

subgroup_data <- xxxx[xxxx$dmuacrgr == 2,]

然后将它用于您的 CPH

cox_model2 <- coxph(Surv(time, status) ~ cov1 + cov2, data = subgroup_data)

然后用

summary

得到危害，CI等

summary(cox_model2)