Disclosed is an interactive user interface of a regression planning and evaluation system, wherein regression planning and evaluation system is employed to obtain audit evidence. The audit evidence is obtained based on input data pertaining to given use case. The interactive user interface comprises: (i) an input interface element that enables user to input audit parameters; and (ii) an output interface element that enables the regression planning and evaluation system to present to user: (a) a regression plot representing a variation of target variable with respect to an explanatory variable, wherein the regression plot indicates an upper and a lower acceptance bounds with respect to regression line, and wherein the regression plot is generated for a plurality of samples based upon input data and audit parameters; and (b) key items, wherein key items are identified as samples that fall outside the upper acceptance bound and the lower acceptance bound in regression plot.