metadat (version 1.4-0)

dat.dogliotti2014: Studies on Antithrombotic Treatments to Prevent Strokes

Description

Results from 20 trials examining the effectiveness of antithrombotic treatments to prevent strokes in patients with non-valvular atrial fibrillation.

Usage

dat.dogliotti2014

Format

The data frame contains the following columns:

study	character	study label
id	numeric	study ID
treatment	character	treatment
stroke	numeric	number of strokes
total	numeric	number of individuals

Author

Guido Schwarzer, , https://github.com/guido-s/

Concepts

medicine, odds ratios, network meta-analysis, Mantel-Haenszel method

Details

This dataset comes from a systematic review aiming to estimate the effects of eight antithrombotic treatments including placebo in reducing the incidence of major thrombotic events in patients with non-valvular atrial fibrillation (Dogliotti et al., 2014).

The review included 20 studies with 79,808 participants, four studies are three-arm studies. The primary outcome is stroke reduction (yes / no).

Examples

### Show first 7 rows / 3 studies of the dataset
head(dat.dogliotti2014, 7)

if (FALSE) {
### Load netmeta package
suppressPackageStartupMessages(library("netmeta"))

### Print odds ratios and confidence limits with two digits
oldset <- settings.meta(digits = 2)

### Change appearance of confidence intervals
cilayout("(", "-")

### Transform data from long arm-based format to contrast-based
### format. Argument 'sm' has to be used for odds ratio as summary
### measure; by default the risk ratio is used in the metabin function
### called internally.
pw <- pairwise(treat = treatment, n = total, event = stroke,
  studlab = study, data = dat.dogliotti2014, sm = "OR")

### Print log odds ratios (TE) and standard errors (seTE)
head(pw, 5)[, 1:5]

### Conduct network meta-analysis (NMA) with placebo as reference
net <- netmeta(pw, ref = "plac")

### Details on excluded study
selvars <- c("studlab", "event1", "n1", "event2", "n2")
subset(pw, studlab == "WASPO, 2007")[, selvars]

### Show network graph
netgraph(net, seq = "optimal", number = TRUE)

### Conduct Mantel-Haenszel NMA
net.mh <- netmetabin(pw, ref = "plac")

### Compare results of inverse variance and Mantel-Haenszel NMA
nb <- netbind(net, net.mh, random = FALSE,
  name = c("Inverse variance", "Mantel-Haenszel"))
forest(nb, xlim = c(0.15, 2), at = c(0.2, 0.5, 1, 2))

### Print and plot results for inverse variance NMA
net
forest(net)

### Use previous settings
settings.meta(oldset)
}