plotdata: Basic function to plot the data of meta-analysis of...

In bamdit: Bayesian Meta-Analysis of Diagnostic Test Data

Basic function to plot the data of meta-analysis of diagnostic test

Description

This function plots the true positive rates vs the false positive rates of each study included in the meta-analysis. Study results are displayed by circles, the diameter of each circle is proportional to the sample size of the study (or table). If subgroups are displayed each group is represented by different colours. This function use the package ggplot2.

Usage

plotdata(
  data,
  two.by.two = FALSE,
  group = NULL,
  x.lo = 0,
  x.up = 1,
  y.lo = 0,
  y.up = 1,
  alpha.p = 0.7,
  max.size = 15
)

Arguments

data	Either a data frame with at least 4 columns containing the true positives (tp), number of patients with disease (n1), false positives (fp), number of patients without disease (n2), or for two.by.two = TRUE a data frame where each line contains the diagnostic results as a two by two table, where the column names are: TP, FP, TN, FN.
two.by.two	If TRUE indicates that the diagnostic results are given as: TP, FP, TN, FN.
group	a variable name indicating a group factor
x.lo	lower limit of the x-axis
x.up	upper limit of the x-axis
y.lo	lower limit of the y-axis
y.up	upper limit of the y-axis
alpha.p	transparency of the points
max.size	scale parameter of the maximum size

Examples

## execute analysis
## Not run: 

data(ct)
ct$design <- with(ct, factor(design,
             labels = c("Prospective", "Retrospective")))

plotdata(ct,              # Data frame
        group = "design", # Groupping variable
        y.lo = 0.75,      # Lower limit of y-axis
        x.up = 0.75,      # Upper limit of x-axis
        alpha.p = 0.5,    # Transparency of the balls
        max.size = 5)     # Scale the circles

## End(Not run)

bamdit documentation built on Sept. 30, 2024, 9:36 a.m.