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help for networkplot command

Title

Plot for networks of interventions in terms of nodes and edges

Description

The networkplot command plots a network of interventions using nodes and edges.
Nodes represent the competing treatments and edges represent the available direct comparisons between pairs of treatments.
It allows for weighting and coloring options for both nodes and edges according to pre-specified characteristics (Chaimani, 2013).
The use of weighting and coloring schemes can reveal important differences in the characteristics of treatments or comparisons;
the latter can be an indication of potential violation of the assumption underlying network meta-analysis (Salanti, 2012),
(Jansen, 2013).

Syntax

networkplot
varlist
[if exp]
[in range]
[,
noweight
nodeweight(study|arm weightvar(s) method)
edgeweight(weightvar method)
labels(string)
labsize(string)
nodecolor(string)
edgecolor(edge_color|by groupvar pool_method)
bylevels(#)
bycolors(string)
edgepattern(string)
plotreg(string)
aspect(#)
edgescale(#)
nodescale(#)
title(string)]

The networkplot command requires in [varlist] to declare the following:

t1 and t2 (numeric or string) the codes of two treatments being compared in every observation of the dataset.

Important note: The networkplot command only reads datasets that have been prepared with network setup or network import in the pairs format

Options

noweight specifies that all nodes and edges (if nodeweight() and edgeweight() have not been specified) are of equal size and thickness.
By default, both nodes and edges are weighted according to the number of studies involved in each treatment or comparison respectively.

nodeweight(study|arm weightvar(s) sum|mean) specifies a study-level variable or two arm-level variables according to which nodes are weighted.

edgeweight(weightvar sum|mean) specifies a variable according to which edges are weighted.

sum|mean specifies whether the sum (the default) or the mean of the values of weightvar is used to weight the nodes and/or edges.

labels(string) specifies the names for treatments in numerical or alphabetical order separated by space. These labels are displayed in the network plot.

labsize(string) specifies the size of the font for treatment labels (see scatter). The the default size is small.

nodecolor(string) specifies the color for all nodes (see scatter). The the default color is blue.

edgecolor(edge_color|by groupvar pool_method)

edge_color specifies the color for all edges (see line). The the default color is black.

by specifies that edges are colored according to the bias level of each comparison.

groupvar is a variable that contains bias scores for each observation (i.e. study data such as effect size) and
can be a numeric variable coded as 1=Low risk, 2=Unclear risk, 3=High risk, or a string variable with values "l(ow)", "u(nclear)", "h(igh)". By default,
a three-level groupvar is assumed. More or less than three levels with user-specified colors are also allowed if the options bylevels and bycolors
have been specified.

pool_method specifies the method to estimate the risk of bias level for the summary estimate of each comparison and can be one of the following:

mode the most prevalent bias level within each comparison is the comparison-specific bias level (the default).

mean the average bias level of each comparison is the comparison-specific bias level.

wmean weightvar the weighted (according to the weightvar) average bias level of each comparison is the comparison-specific bias level.

max the maximum bias level observed within each comparison defines the comparison-specific bias level.

min the minimum bias level observed within each comparison defines the comparison-specific bias level.

bylevels(#) specifies the number of levels for the groupvar in edgecolor() when there are more than 3 bias levels. In this
case the groupvar variable can be only numeric and the option bycolors is required.

bycolors(string) specifies the colors for each bias level of the groupvar in the respective order (the option bylevels() is required).

edgepattern(string) specifies the pattern for all edges (see line).

plotreg(string) specifies options for the region of the network plot (see graph). The the default option is margin(15 15 10 10).

aspect(#) specifies the aspect ratio for the region of the network plot (see aspectratio). The default is 1.

edgescale(#) specifies a real number that is used to scale all edges

nodescale(#) specifies a real number that is used to scale all nodes

title(string) specifies the title of the plot.

Examples

. networkplot treat1 treat2, noweight

. networkplot treat1 treat2, nodew(study number_patients) edgew(baseline_risk)

. networkplot treat1 treat2, edgecolor(by wmean inverse_variance) labels(Placebo Aspirin Dipyridamole)

. networkplot treat1 treat2, edgecolor(by inverse_variance) bylevels(5) bycolors(green blue magenta sienna purple)

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