forest.umbrella {metaumbrella}

Forest plots for “umbrella” objects

Description

Draw a forest plot of the factors included in an umbrella review. This function is now a wrapper around the amazing forest.meta function designed by Guido Schwarzer and Gerta Rucker. You can thus add any other arguments available in the forest.meta function but not detailed here.

Usage

## S3 method for class 'umbrella'
forest(
  x,
  layout = "meta",
  measure = "auto",
  leftcols = NULL,
  leftlabs = NULL,
  rightcols = NULL,
  rightlabs = NULL,
  digits = 2,
  smlab = "",
  xlab = NULL,
  type.study = "square",
  print.classes = FALSE,
  subgroup = NULL,
  subgroup.name = "",
  col.square = "gray",
  col.study = "black",
  col.square.lines = "black",
  fontsize = 12,
  spacing = 1,
  squaresize = 0.8/spacing,
  ...
)

Arguments

x

an object of class “umbrella” or a or “data.frame” object returned by the umbrella() or add.evidence() functions.

layout

type of layout of the plot ("meta", "JAMA" or "RevMan5").

measure

type of effect size used in the plot ("eG", "eOR", "raw" or "auto"). Default is the most frequently used effect size measure.

leftcols

vector of columns contained in the object passed to the x argument, used to specify columns which are printed on the left side of the forest plot.

leftlabs

vector of column names used to specify column names printed on the left side of the forest plot.

rightcols

vector of columns contained in the object passed to the x argument, used to specify columns which are printed on the right side of the forest plot.

rightlabs

vector of column names used to specify column names printed on the left side of the forest plot.

digits

number of digits to display

smlab

character string describing the title of the plot

xlab

character string describing the x-axis title

type.study

the shape used to depict the pooled effect size (must be either "square", "diamond", or "predict")

print.classes

a vector of classes. Only factors reaching these classes will be displayed on the plot. These classes must be "I", "II", "III", "IV" and/or "ns" for the "Ioannidis" classification, or "High", "Moderate", "Weak" and/or "Very weak" for the "GRADE" classification, or "I", "II", "III", "IV", and/or "V" for the "Personalized" classification

subgroup

a character variable indicating the name of the column that should be used as header for creating subgroups between the factors

subgroup.name

a character variable displayed just before each modality of the subgroup variable

col.square

The colour for squares reflecting study's weight in the meta-analysis.

col.study

The colour for individual study results and confidence limits.

col.square.lines

The colour for the outer lines of squares reflecting study weight in the meta-analysis.

fontsize

The size of text (in points)

spacing

A numeric variable determining line spacing in a forest plot.

squaresize

A numeric variable used to increase or decrease the size of squares in the forest plot.

...

additional arguments that can be passed to the forest.umbrella function

Details

The function allows to have a visualization of the results of an umbrella review. Various parameters, such as the type of effect size displayed, the restriction to some classes or the color of the dots, allows to simplify the visualization.

Value

Return a forest plot of the pooled effect sizes, along with additional information

References

Balduzzi S, Rucker G, Schwarzer G (2019). How to perform a meta-analysis with R: a practical tutorial. Evidence-Based Mental Health, 153–160.

Examples

### perform an umbrella review
umb <- umbrella(df.OR)

### generate a forest plot of each factor included in the umbrella review
forest(umb)

## Not run: 
forest(umbrella(df.SMD))

## End(Not run)