The phase-shift method and correlation constants, i.e., the electrochemical impedance spectroscopy (EIS) techniques for studying the linear relationship between the behavior (-phi vs. E) of the phase shift (0 degrees <= -phi <= 90 degrees) for the optimum intermediate frequency and that (theta vs. E) of the fractional surface coverage (1 >= theta >= 0), have been proposed and verified to determine the Langmuir, Frumkin, and Temkin adsorption isotherms of hydrogen and related electrode kinetic and thermodynamic parameters at the interfaces. This paper is a correction and supplement to our previously published papers [Chun JH, Jeon SK, Kim BK, Chun JY. Determination of the Langmuir adsorption isotherms of under- and over-potentially deposited hydrogen for the cathodic H-2 evolution reaction at poly-Ir/aqueous electrolyte interfaces using the phase-shift method. Int J Hydrogen Energy 2005;30(3):247-59. Chun JH, Jeon SK, Kim NY, Chun JY. The phase-shift method for determining Langmuir and Temkin adsorption isotherms of over-potentially deposited hydrogen for the cathodic H-2 evolution reaction at the poly-Pt/H2SO4 aqueous electrolyte interface, Int J Hydrogen Energy 2005;30(13-14):1423-36.]. The lack of a Gaussian analysis for the rates of change of -phi vs. E and theta vs. E for the optimum intermediate frequency results in an unclear conclusion. (C) 2008 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.