Correctly fitting hearing aids. Hearing aid fitting is an important part of hearing rehabilitation. The degree of deafness varies from person to person. Hearing aids are a means to help patients make effective use of their residual hearing. Therefore, it is important for the patient to go to a professional institution for proper fitting so that the hearing aid can be used to maximum effect. The most basic method of audiological examination is pure tone audiometry, which aims to clarify the hearing status of the user and to use it as a basis for proper selection of hearing aids. Routine examinations help to exclude cases that require active treatment (e.g., auditory neuroma, chronic otitis media, etc.). 2. Determine whether to use hearing aids unilaterally or bilaterally Whenever possible, hearing aids should be worn in both ears. It is beneficial to improve the hearing discrimination, hearing comfort and hearing direction discrimination. 3. Determine the type of hearing aid Cartridge, behind-the-ear, customized in-the-ear and canal hearing aids are the most common types, each with its own advantages and disadvantages in terms of performance, price, wearing comfort and ease of operation. Generally speaking, it is better to choose customized hearing aids. As for the choice of electroacoustic performance, the experience of the dispenser may be of greater help to the patient. 4.Subjective feeling and adaptation Since hearing is a very complex feeling, it is impossible for an experienced fitter to be 100% accurate. According to years of experience in hearing aid fitting, the factors that affect the subjective feeling of hearing aids may be: the quality of the hearing aid, digital technology or analog technology, the experience of the fitter, the patient’s acceptance of the hearing aid and other reasons. Most users will have a gradual adaptation process to the hearing aid. If the hearing is very poor, once the hearing aid is worn, the patient will feel that the surrounding sound is very noisy. This is the patient has already adapted to the quiet surrounding state, and once they are exposed to the sound, they will incorporate the tiny sounds around them that they could not hear at all before into their ears, and they cannot adapt immediately subjectively. If they consciously carry out adaptation training, they will feel that the hearing aid effect is getting better. 5. Re-adjustment After a period of adaptation, some users may feel slightly uncomfortable with the initially determined electroacoustic performance parameters, which is normal, and ask the hearing aid dispenser to help adjust them.