Moving from input-based to outcome-based welfare assessment represents the frontier of welfare science — measuring what animals actually experience rather than what resources they are provided.
The shift from input to outcome measurement is transforming welfare science. Knowing that a farm provides perches tells us little about whether hens actually use them and benefit from doing so. Knowing that 3% of hens have keel bone fractures tells us precisely how many are in pain. Outcome-based welfare assessment — measuring injuries, disease, behavioral indicators, and physiological markers — directly captures animal experience rather than management intention.