1. A method comprising: determining, based on an estimated number of errors for a code word received by an error correcting code (ECC) decoder, whether to obtain an indication of accuracy for data values of the received code word; and correcting one or more errors in the received code word based on the accuracy indication using the ECC decoder, in response to determining to obtain the accuracy indication, by assigning scores to the data values based on the accuracy indication, the score for a data value indicating a probability that the data value is in error, and updating the scores based on relationships between the data values, the relationships described by a parity check matrix.