A method of reading a memory device that includes a memory cell that stores data of at least two bits includes determining whether a cell resistance level is no greater than a threshold resistance level. If the cell resistance level is smaller than or equal to the threshold resistance level, then the data is read based on a first factor that is inversely proportional to the cell resistance level. If the cell resistance level is greater than the threshold resistance level, then the data is read based on a second factor that is proportional to the cell resistance level.