  The statistical combination of disjoint signal regions in reinterpretation
studies uses more of the data of an analysis and gives more robust results than
the single signal region approach. We present the implementation and usage of
signal region combination in MadAnalysis 5 through two methods: an interface to
the pyhf package making use of statistical models in JSON-serialised format
provided by the ATLAS collaboration, and a simplified likelihood calculation
making use of covariance matrices provided by the CMS collaboration. The gain
in physics reach is demonstrated 1.) by comparison with official mass limits
for 4 ATLAS and 5 CMS analyses from the Public Analysis Database of MadAnalysis
5 for which signal region combination is currently available, and 2.) by a case
study for an MSSM scenario in which both stops and sbottoms can be produced and
have a variety of decays into charginos and neutralinos.
