Autism, or loneliness, can be checked and examined in several ways, including physical examination, psychiatric examination, psychological assessment scales, and ancillary examinations. Specifically as follows: 1. Physical examination: the child’s physical development, such as the presence of congenital malformations, visual and auditory impairments, neurological impairments, height, weight, head circumference and facial features. 2. Psychiatric examination: A comprehensive psychiatric examination to understand the child’s developmental level and to determine whether there are any abnormalities in the child’s social interaction, verbal and non-verbal communication, interest behavior, cognitive development and other mental activities. 3. Psychological assessment scales: Commonly used screening childhood autism scales include the Modified Infant and Child Autism Scale (M-CHAT), the Autism Behavioral Checklist for Children (ABC), and the Kirschner Autism Behavioral Scale (CABS). Commonly used scales for diagnosing childhood autism include: Childhood Autism Rating Scale (CARS), Autism Diagnostic Observation Scale (ADOS), etc. Commonly used developmental and intelligence assessment scales include: Wechsler Intelligence Scale for Children (WISC), Denver Developmental Screening Test (DDST) and so on. 4. Auxiliary tests: electroencephalogram (EEG), imaging tests (cranial CT, cranial magnetic resonance), genetics-related tests (karyotyping), and metabolic disease screening. It should be reminded that for children suspected of autism, it is recommended that family members accompany the patient to the hospital for a comprehensive and standardized examination, so as to avoid delaying the condition and causing adverse consequences.