Integrated circuit memory devices include an array of nonvolatile N-bit memory cells, where N is an integer greater than one. Control circuitry is also provided to reliably read data from the N-bit memory cells. This control circuitry, which is electrically coupled to the array, is configured to determine, among other things, a value of at least one bit of data stored in a selected N-bit memory cell in the array. This is done by decoding at least one hard data value and a plurality of soft data values (e.g., 6 data values) read from the selected N-bit memory cell using a corresponding plurality of unequal read voltages applied to the selected N-bit memory cell during a read operation.