  Finding out universal conditions describing the freeze-out parameters was a
subject of various phenomenological studies. In the present work, we introduce
a new condition based on constant trace anomaly (or interaction measure)
calculated in the hadron resonance gas (HRG) model. Various extensions to the
{\it ideal} HRG which are conjectured to take into consideration different
types of interactions have been analysed. When comparing HRG thermodynamics to
that of lattice quantum chromodynamics, we conclude that the hard-core radii
are practically irrelevant, especially when HRG includes all resonances with
masses less than $2~$GeV. It is found that the constant trace anomaly (or
interaction measure) agrees well with most of previous conditions.
