I. Routine assessment items (a) Medical history The diagnosis of ED is mainly based on the patient’s complaints, so obtaining an objective and accurate history is the key to the diagnosis of the disease. The patient’s shyness, embarrassment and difficulty in speaking should be eliminated. The patient’s spouse should be encouraged to participate in the diagnosis and treatment of ED. 1, sexual life history, marital and reproductive status (1) sexual function assessment: how is the libido? Can the penis be erected under sexual stimulation? Is it hard enough for penetration? Can it last long enough? Is there any ejaculatory dysfunction such as premature ejaculation? Are there any abnormalities of orgasm? Occasional failure of sexual intercourse cannot be easily diagnosed as ED. (2) ED onset and course: Is the onset of ED sudden or slow, and is the degree of ED gradually aggravated? Is ED associated with sexual scenarios, are there morning erections, etc.? (3) The severity of ED: The severity of ED can be categorized as mild, moderate and severe (complete). Due to the strong subjectivity of ED diagnosis, the International Index of Erectile Function-5 (IIEF-5) (Exhibit 1) or the Chinese Index of Erectile Function-5 (IIEF-5) (Exhibit 2) are used in clinical practice. Chinese Index of Erectile Function5 (CIEF-5) (Exhibit 2) to objectively assess the severity of ED. Penile erection hardness was graded according to the following categories: 1 extreme, penis only swells but is not hard as severe ED; 2 grade, hardness is not enough to penetrate into the vagina as moderate ED; 3 grade, can penetrate into the vagina but is not firm as mild ED; and 4 grade, erection is firm as normal erectile function. (4) Non-coital penile erection status: past and present penile erection at night and in the morning when waking up, sexual fantasy or visual, auditory, olfactory and tactile stimulation with or without penile erection. (5) Whether the mental, psychological, social and family factors affect the erectile function: whether there is any negative influence and mental trauma in the process of development, whether there is any marital conflict in adulthood, sexual partner disharmony, lack of communication; accidental ups and downs, great pressure at work, economic embarrassment, tense interpersonal relationship, external interference during sexual intercourse; one’s own bad feelings, doubts about one’s own sexuality, low self-esteem; sexual ignorance or wrong knowledge of sexuality; religion and feudalistic consciousness. Influence and so on. (2) ED-related diseases and injuries (1) Systemic diseases Systemic diseases: cardiovascular disease, hypertension, hyperlipidemia, diabetes mellitus and liver and kidney insufficiency. Neurological diseases: multiple cirrhosis, myasthenia gravis, cerebral atrophy and sleep disorders. Reproductive system diseases: penile deformity, sclerodactyly and prostate diseases, etc. Endocrine disorders: hypogonadism, hyperprolactinemia, abnormal thyroid function, etc. Psychological disorders: depression, anxiety, fear and guilt, etc. (2) Injuries Neurological injuries: spinal cord injury, traumatic brain injury, sympathectomy. Pelvic and perineal injuries; including genital and pelvic trauma, urethra and prostate surgery, pelvic organ surgery, retroperitoneal lymph node dissection, and pelvic radiation therapy. 3, ED-related drugs and poor lifestyle (1) Some drugs for high blood pressure, heart disease, diabetes, central nervous system diseases, antidepressants, and anti-androgen drugs, H2 receptor blockers and anticholinergic drugs. (2) Abuse of narcotic drugs. (3) Smoking. (4) Alcohol abuse. （Physical examination Focus on secondary sexual characteristics, peripheral blood vessels, reproductive system and nervous system. 1, the second sex development: pay attention to the patient’s skin, body shape, bone and muscle development, the presence or absence of laryngeal nodes, beard and body hair distribution and density, the presence or absence of male mammary gland development. 2, peripheral vascular examination: pay attention to touch the femoral artery, dorsalis pedis artery and dorsal penile artery is small, need to touch carefully. The patient takes the lying position, puts the finger gently on the root of the dorsal side of the penis to touch the arterial pulsation. In arteriosclerosis, trauma and elderly men, the pulsation is weakened or disappeared. 3.Reproductive system examination: pay attention to the size of the penis, whether there are deformities and hard nodules, and whether the testicles are normal. 4.Nervous system examination: perineal sensation, abdominal wall reflex, elevator muscle reflex, knee reflex, bulbocavernosus muscle reflex and so on. Globus cavernosus muscle reflex examination method: the patient’s knee and chest position, the examiner’s right index finger into the anus, to understand the anal sphincter muscle tension. When the patient’s anal sphincter relaxes, the head of the penis is quickly squeezed with the two fingers of the left hand, and the right index finger located in the anus can feel the reflexive contraction of the sphincter, and if the reflex is weak or there is no reflex, it suggests that the neurological reflexes are impaired. (C) Laboratory examination 1, blood routine. 2.Urinary routine. 3, blood biochemistry: including blood sugar, liver and kidney function and blood lipid. (4) Hypothalamic-pituitary-testicular gonadal axis function test: mainly detecting serum total testosterone (tT), free testosterone (fT), prolactin (PRL), follicle stimulating hormone (FSH) and luteinizing hormone (LH) levels. Recommended assessment items can be used for those who need to implement appropriate invasive treatment when oral medication is ineffective, or those who need to clarify the etiology of ED and those who are involved in legal and accident identification. （Nocturnal penile tumescence (NPT) monitoring Nocturnal penile tumescence is a physiological phenomenon in healthy men from infancy to adulthood, and it is an important method to identify psychogenic and organic ED in clinical practice. 1.Hardness tester (RiqiScan): RiqiScan is a device that can continuously record the degree of nocturnal penile distension, hardness, number of erections and duration, and can be monitored at home. 2.Nocturnal electrobioimpedance volumetric assessment (NEVA): The NEVA device is used to detect the changes in blood flow before and after the erection of the penis, resulting in electrical resistance and understanding of the erection. (ii) Penile cavernous injection of vasoactive drugs test (intracavernous injevtion, ICI) Penile cavernous injection of vasoactive drugs test is mainly used to identify vascular, psychological and neurological ED. (iii) Penile color Doppler uitrasonography (color Doppler uitrasonography, CDU) CDU is one of the most valuable methods currently used to diagnose vascular ED. The patient goes to the supine position, the ultrasound probe is placed on the dorsal side of the penis, and the anatomical structure of the penis is first observed to know whether there is vascular calcification, cavernous fibrosis and hardness, etc. After that, the penile anatomy is observed before and after the injection of vasoactive drugs. After that, observe the changes of penile blood vessels and blood flow before and after injection of vasoactive drugs, commonly used drugs are prostaglandin E1, poppycock and phentolamine. (c) Optional evaluation items (a) Penile cavernosography (Cavernosography): Penile cavernosography is used to diagnose venous ED. (b) Selective pudendal arteriography (selective pudendal arteriography) Selective pudendal arteriography can clarify the site and extent of arterial lesions. However, this technique should be used with caution as it is not absolutely safe and can result in complications such as bleeding or arterial endothelial stripping. Penile corpus cavernosum manometry, bulbocavernosus muscle reflex latency time, sciatica cavernosus muscle reflex latency time and sensory threshold determination are not commonly used.