We have recently shown that the inclusion of finite-size volume corrections for the hadrons in the hadronic gas phase drastically alters the conclusions regarding isothermal baryon-number fluctuations arising from a first-order quark-hadron phase transition in the early Universe. In this paper we compare in detail the predictions of various existing thermodynamically consistent hadron gas (HG) models for the baryon density in the HG phase and its dependence on the temperature in order to draw a firm conclusion regarding the results obtained in the earlier paper. \textcopyright{} 1996 The American Physical Society.