We have previously developed a population balance equation (PBE) model for emulsion drop breakage in a high-pressure homogenizer that incorporated multiple-drop formation within two mechanisms of turbulent drop breakage. The model was found to satisfactorily predict the effects of formulation variables on the drop-size distribution, but the model was not extensible to a range of homogenization pressures. The objective of this paper is to determine the additional model elements necessary to obtain acceptable predictions over a wide range of pressures. The most significant improvements were obtained by increasing the number of daughter drops formed upon breakage from 20 to 150 drops and by introducing a maximum stable diameter, below which drops could not break. Smaller improvements were obtained by introducing terms that describe the loss of energy available for drop breakage due to thermal heating of the sample and homogenizer and by extending the model to account for the effects of surfactant adsorption and deficiency on the interfacial tension. The simultaneous implementation of all five enhancements was shown to produce a 62% improvement over the previous model, as measured by a least-squares objective based on the difference between the measured and predicted drop-size distributions over five homogenization passes and five pressures in the range 250-1250 bar. The resulting model was also validated over a range of oil and surfactant concentrations and shown to provide satisfactory predictions.