Correlations with experimental factors. (A) Mean midpoint of activation, μ_a, and inactivation, μ_i, in studies that report correcting for the LJP, that report not correcting, and that do not report on LJP correction. (B and C) μ_a and μ_i versus the holding potential in the activation and inactivation protocols, respectively. A regression line is shown, along with the number of studies for which this data were available, n, and the coefficient of determination, r². (D) We saw no correlation between μ_a and the steepness of the activation curve, k_a. (E) The voltage at which the peak current occurred during the activation protocol correlates strongly with the reported μ_a.