  We present an effective model for the generic behaviour of hadron masses and
phase shifts at finite temperature which shares basic features with recent
developments within the PNJL model for correlations in quark matter. On this
basis we obtain the transition between a hadron resonance gas phase and the
quark gluon plasma in the spirit of the generalized Beth-Uhlenbeck approach
where the Mott dissociation of hadrons is encoded in the hadronic phase shifts.
Here we restrict ourselves to low-lying hadronic channels and perform a
discussion of recent lattice QCD thermodynamics results from this perspective.
We find agreement in the asymptotic regions while for the description of the
transition itself the inclusion of further hadronic channels as well as a
selfconsistent determination of the continuum thresholds is required.
