A method for assessing an effect, such as a treatment, disease, or passage of time on a cellular unit of an organism includes providing a sample including a cellular unit subject to the effect in a supporting medium in a hermetically sealed container. The container is deoxygenated to induce at least one of a predetermined amount of hypoxia and a predetermined rate of oxygen consumption in the medium. Values for variables associated with the medium and/or the cellular unit are determined at each of a plurality of different times. Various combinations of the predetermined amount of hypoxia, the predetermined rate of oxygen consumption, the values for the variables associated with the medium and/or cellular unit, and the times and then correlated to generate a multi-dimensional surface. This surface is compared with another surface correlating corresponding values relating to another cellular unit such as one not subject to the effect.