Table 2 Mean Square Error (MSE) comparison for B-spline, P-spline and fractional polynomial (FP) network meta-analysis models. Displayed are the mean and standard deviation (SD) of the respective MSEs averaged over 50 simulated data sets for each scenario. Unless stated otherwise, considered outcomes are continuous. Scenarios that contain non-monotonic temporal behaviors appear to be challenging for the FP method

Linear

0.0019

0.0213

0.0021

0.0243

0.3505

0.0388

Logarithmic

0.0014

0.0111

0.0015

0.0135

0.3505

0.0118

Piecewise linear monotonic

0.0011

0.0923

0.0052

0.1437

1.3069

0.1823

Mixed

0.0037

0.0313

0.0040

0.0931

1.5747

0.1338

Non-monotonic

0.0019

0.0389

0.0027

0.1039

41.7533

1.8354

MTC

0.0374

0.0483

0.0402

0.0984

0.9198

0.2864

BEST-ITC

0.0397

0.0503

0.0402

0.1003

0.1701

0.2898

Piecewise linear monotonic (binary)

0.0034

0.0118

0.0053

0.0978

0.0897

0.3698

Non-monotonic (binary)

0.0004

0.0019

0.0004

0.0178

0.9748

0.2976

Piecewise linear (non-closed network)

0.0172

0.0173

0.0235

0.0774

0.0903

0.3854