  Techniques for performing model-independent searches for direct CP violation
in three and four-body decays are discussed. Comments on the performance and
the optimisation of a binned chisquare approach and an unbinned approach, known
as the energy test, are made. The use of the energy test in the presence of
background is also studied. The selection and treatment of the coordinates used
to describe the phase-space of the decay are discussed. The conventional
model-independent techniques, which test for P-even CP violation, are modified
to create a new approach for testing for P-odd CP violation. An implementation
of the energy test using GPUs is described.
