更改包元数据林图中的置信区间格式?

时间:2016-08-10 04:40:58

标签: r plot confidence-interval

假设下面的代码(如Viechtbauer,2010中所示):

library(metafor)
data("dat.bcg", package = "metafor")
dat <- escalc(measure = "RR", ai = tpos, bi = tneg, ci = cpos, di = cneg, data = dat.bcg, append = TRUE)
res <- rma(ai = tpos, bi = tneg, ci = cpos, di = cneg, data = dat, measure = "RR")
forest(res, slab = paste(dat$author, dat$year, sep = ", "), xlim = c(-16, 6), at = log(c(0.05, 0.25, 1, 4)), atransf = exp, ilab = cbind(dat$tpos, dat$tneg, dat$cpos, dat$cneg), ilab.xpos = c(-9.5, -8, -6, -4.5), cex = 0.75)
op <- par(cex = 0.75, font = 2)
text(c(-9.5, -8, -6, -4.5), 15, c("TB+", "TB-", "TB+", "TB-"))
text(c(-8.75, -5.25), 16, c("Vaccinated", "Control"))
text(-16, 15, "Author(s) and Year", pos = 4)
text(6, 15, "Relative Risk [95% CI]", pos = 2)
par(op)

这给出了如下森林图:

Forest plot

那么如何更改图表中置信区间的格式呢?是否可以用括号替换括号并使用&#34;到&#34;而不是&#34;,&#34;?如何使用&#34; - &#34;或长期宣传而不是&#34;,&#34;?这应该改变,即[0.13,1.26]至(0.13至1.26)或(0.13 - 1.26)

2 个答案:

答案 0 :(得分:5)

您需要对forest.rma的代码进行一些黑客攻击。几个步骤:

通过输入函数名称显示当前版本的代码:

 forest.rma   # Copy the name and the code and paste into the console 
              #  Add an assignment operator `<-`
              # leave off the bytecode and environment notations at the bottom

或者您可以在编辑器中执行此操作,这可能是首选方法,因为您可能希望将此代码保存到.Rprofile文件。

1)将参数添加到参数列表中:

forest.rma <- 
function (x, annotate = TRUE, addfit = TRUE, addcred = FALSE, 
    showweights = FALSE, xlim, alim, clim, ylim, at, steps = 5, 
    level = x$level, digits = 2, refline = 0, xlab, slab, mlab, 
    ilab, ilab.xpos, ilab.pos, order, transf, atransf, targs, 
    rows, efac = 1, pch = 15, psize, col, border, lty, cex, cex.lab, 
    cex.axis, annosep = " , ", bkt=c("[", "]"), ...) 
{  #  ....not showing all the _long_ function body 
   # Scroll down to almost the bottom of the function body

2)查找并更改annotext cbind - 赋值的参数。有几个地方可能会构建annotext,但只有其中一个匹配您的&#34;格式目标&#34;。找到一个看起来像这样的人:

# annotext <- cbind(annotext[, 1], " [ ", annotext[, 
#                2], " , ", annotext[, 3], " ]")

更改为:

annotext <- cbind(annotext[, 1], bkt[1], annotext[, 
                 2], annosep, annotext[, 3], bkt[2] )
# hit enter to get the modification to hold in your workspace

3)现在为函数分配正确的环境,以便它可以与兄弟姐妹很好地配合:

environment(forest.rma) <- environment(forest.default)
# if you forget this step you see this error:
  

forest.rma中的错误(res,slab = paste(dat $ author,dat $ year,sep =&#34;,&#34;),:     找不到功能&#34; .setlab&#34;

并使用您选择的新参数调用它:

png(); forest(res, slab = paste(dat$author, dat$year, sep = ", "), xlim = c(-16, 6), at = log(c(0.05, 0.25, 1, 4)), atransf = exp, ilab = cbind(dat$tpos, dat$tneg, dat$cpos, dat$cneg), ilab.xpos = c(-9.5, -8, -6, -4.5), cex = 0.75, annosep=" to ", bkt = c( "(", ")" ) )
op <- par(cex = 0.75, font = 2)
text(c(-9.5, -8, -6, -4.5), 15, c("TB+", "TB-", "TB+", "TB-"))
text(c(-8.75, -5.25), 16, c("Vaccinated", "Control"))
text(-16, 15, "Author(s) and Year", pos = 4)
text(6, 15, "Relative Risk [95% CI]", pos = 2)
dev.off()

enter image description here

答案 1 :(得分:2)

这是一个不需要更改forest.rma()函数代码的解决方案。我使用annotate=FALSE,以便该函数不会注释森林图,而是自己添加这些注释。

library(metafor)
data("dat.bcg", package = "metafor")
dat <- escalc(measure = "RR", ai = tpos, bi = tneg, ci = cpos, di = cneg, data = dat.bcg, append = TRUE)

res <- rma(ai = tpos, bi = tneg, ci = cpos, di = cneg, data = dat, measure = "RR")

### note the use of annotate=FALSE in forest()
forest(res, slab = paste(dat$author, dat$year, sep = ", "), xlim = c(-16, 6), 
       at = log(c(0.05, 0.25, 1, 4)), atransf = exp, 
       ilab = cbind(dat$tpos, dat$tneg, dat$cpos, dat$cneg), ilab.xpos = c(-9.5, -8, -6, -4.5), 
       cex = 0.75, annotate=FALSE) 

op <- par(cex = 0.75, font = 2)
text(c(-9.5, -8, -6, -4.5), 15, c("TB+", "TB-", "TB+", "TB-"))
text(c(-8.75, -5.25), 16, c("Vaccinated", "Control"))
text(-16, 15, "Author(s) and Year", pos = 4)
text(6, 15, "Relative Risk [95% CI]", pos = 2)

### add annotations manually
tmp <- summary(dat, transf=exp)[,c("yi","ci.lb","ci.ub")] ### for the individual studies
tmp <- rbind(tmp, with(predict(res, transf=exp), c(pred, ci.lb, ci.ub))) ### add model estimate and CI bounds
sav <- apply(tmp, 2, formatC, format="f", digits=2)
annotext <- apply(sav, 1, function(x) {paste0(x[1], " (", x[2], " to ", x[3], ")")})
text(6, c(res$k:1, -1), annotext, pos=2, font=1)

par(op)