Benefiting from strong decoding capabil-ities, soft-decision decoding has been used to replace hard-decision decoding in various communication sys-tems, and NAND flash memory systems are no excep-tion. However, soft-decision decoding relies heavily on accurate soft information. Owing to the incremen-tal step pulse programming (ISPP), program errors (PEs) in multi-level cell (MLC) NAND flash memory have different characteristics compared to other types of errors, which is very difficult to obtain such accu-rate soft information. Therefore, the characteristics of the log-likelihood ratio (LLR) of PEs are investigated first in this paper. Accordingly, a PE-aware statistical method is proposed to determine the usage of PE mit-igation schemes. In order to reduce the PE estimating workload of the controller, an adaptive blind clipping (ABC) scheme is proposed subsequently to approxi-mate the PEs contaminated LLR with different decod-ing trials. Finally, simulation results demonstrate that (1) the proposed PE-aware statistical method is effec-tive in practice, and (2) ABC scheme is able to provide satisfactory bit error rate (BER) and frame error rate (FER) performance in a penalty of negligible increas-ing of decoding latency.