A method for reducing brightness uniformity variations in an active-matrix OLED display employing amorphous silicon thin-film transistors, by providing an active-matrix OLED display having amorphous silicon thin-film transistors; and deriving a first correction value from a measured or estimated value of light-emitting element performance. Subsequently groups of light-emitting elements are identified, whereupon one or more representative light-emitting elements are selected. Remaining steps include measuring total representative current used by the representative light-emitting elements for each predetermined group of light-emitting element; deriving an estimated second correction value from the first correction value, or the measured or estimated value of light-emitting element performance, and the measured total representative currents for each individual light-emitting elements; and employing the estimated second correction value to correct image signals for the changes in the output of the light-emitting elements and produce compensated image signals.