is_network_connected function

Check network connectedness

Check whether a network is connected - whether there is a path of study evidence linking every pair of treatments in the network.

is_network_connected(network)

Arguments

• network: An nma_data object, as created by the functions set_*() or combine_network().

Returns

Logical TRUE or FALSE

Details

Models will still run with disconnected networks. However, estimated relative effects between treatments across disconnected parts of the network will be entirely based on the prior distribution (typically very uncertain), as there is no information to update the prior distribution. Relative effects within each connected sub-network will be estimated as if each sub-network had been analysed separately.

Examples

## Smoking cessation
# Set up network of smoking cessation data
head(smoking)

smk_net <- set_agd_arm(smoking,
                       study = studyn,
                       trt = trtc,
                       r = r,
                       n = n,
                       trt_ref = "No intervention")

# Print details
smk_net

is_network_connected(smk_net)  # TRUE, network is connected
## A disconnected network
disc_net <- set_agd_arm(smoking[smoking$studyn %in% c(15, 21), ],
                        study = studyn,
                        trt = trtc,
                        r = r,
                        n = n)
is_network_connected(disc_net)  # FALSE, network is disconnected
disc_net
plot(disc_net)