Hearing loss can impair auditory discrimination, especially in noisy environments, requiring greater listening effort, which can impact socio-occupational life. To assess the impact of hearing loss in noisy environments, clinicians may use subjective or objective methods. Subjective methods, such as speech audiometry in noise, are used in clinical practice to assess reported discomfort. Objective methods, such as cortical auditory evoked potentials (CAEPs), are mainly used in research. Subjective methods mainly comprise speech audiometry in noise, in which the signal-to-noise ratio can be varied so as to determine the individual speech recognition threshold, with and without hearing rehabilitation, the aim being to highlight any improvement in auditory performance. Frequency discrimination analysis is also possible. Objective methods assess auditory discrimination without the patient's active participation. One technique used for patients with auditory rehabilitation is the study of auditory responses by CAEPs. This electrophysiological examination studies cortical auditory rehabilitation oddball paradigms, enabling wave recordings such as mismatch negativity, P300 or N400, and analysis of neurophysiological markers according to auditory performance. The present article reviews all these methods, in order to better understand and evaluate the impact of hearing loss in everyday life.