Note that the linear correlation coefficient, r, describes the conformity of the data to the median effect principle.
To determine the nature of combination of the two drugs, the median effect principle outlined by Chou [ 55] was utilized.
The type of drug interaction was determined by the median effect principle according to the method of Chou and Talalay [ 27] and was applied for the three-drug treatment [ 28].
Later versions of the double effect principle all emphasize the distinction between causing a morally grave harm as a side effect of pursuing a good end and causing a morally grave harm as a means of pursuing a good end.
The effects on cell growth were measured in cell based assays using the fixed molar ratio design and the median effect principle.
The cytotoxic activity was evaluated by sulphorhodamine B assay and the type of drug interaction was assessed by the median effect principle.
The effect of drug combinations was calculated according to the median effect principle described by Chou and Talalay (1984).
Using the median effect principle of mass action, it was possible to calculate the expected effect of a combination of drugs based on knowledge of their individual effects.
The median effect principle of mass action states that where D is the drug dose, Dm the drug dose required for 50% cell kill, fa the cell fraction affected, fu the cell fraction unaffected, and m the coefficient of sigmoidicity.
Drug combination effects were determined using the Chou and Talalay method (Chou and Talalay, 1984) based on the median effect principle.
