A method includes performing a first read operation on a memory cell of a programmed first one-time programmable (OTP) anti-fuse to determine a state of the memory cell based on a first parameter level, performing a second read operation on the memory cell of the programmed first OTP anti-fuse to determine the state of the memory cell based on a second parameter level, identifying the memory cell of the first OTP anti-fuse as an uncertain bit when the state determined during the first read operation and the state determined during the second read operation are different, and programing one or more memory cells of a second OTP anti-fuse based on a bit position of the identified uncertain bit of the first OTP anti-fuse.