Methods, apparatus and computer program products are provided for encoding and/or decoding a data block. The method for encoding a data block includes the steps of: providing an information block of size k, I=(i0, i1, . . . i(k−l); and encoding the information block into a low-density parity-check (LDPC) codeword c of size n, c=(i0, i1, . . . i(k−l), p0, p1, . . . , p(n−k−l)), by adding n−k parity bits obtained so that H·cT=0, where H is an (n−k)×n parity-check matrix.