Table 1.

Criteria and sub-criteria applied to evaluate the utility of biomass denominators in the FDA, ESVAC, PHAC and OIE methodologies

Criteria	Sub-criteria	Notation	Definition
Level of detail (resolution) accounted for in the estimated animal biomass (Which biomass estimate provides the highest resolution in the estimated US livestock biomass?)	Granularity	G	Number of specific animal production categories considered for each species
	Comprehensiveness	C	Capacity to collect population data for all animals of a species
	Accuracy	A	Use of actual treatment weight data per species
Comparability: practicality in biomass estimation for comparison across countries (Can we estimate animal biomass to compare sales across countries?)	Standardized parameters	Sp	Use of standardized values for estimating animal biomass
	Data uniformity	Du	Availability of centralized sources for data collection
Ability of observing trends in animal biomass within a country (Can we observe trends over time?)	Stability in population	So	Size and structure of population at risk of being treated correct for changes over time
	Stability in weights	Sw	Weight of animals at risk of being treated correct for changes over time