Deriving the Types and Characteristics of Lost Children in South Korea Using the Sequential Association Rule

The studies that examine the characteristics of lost children and identify the types and processes of children being lost are insufficient. Therefore, this study aimed to establish the fundamental types and characteristics of lost children and develop a plan for their prevention. First, the common patterns of lost children were derived via the “sequential association rule” using the lost child case data from the previous studies. Next, the lost child types were derived by examining the patterns of lost children, focusing on the situation (conditions) before the child was lost and the causes. Additionally, a series of processes leading to children getting lost and being reunited with their guardians, according to the lost child type, were systematized. Finally, the causes and characteristics of lost children were derived for each type. The following types of lost children were derived: type I—when a child unexpectedly breaks away from the guardian and becomes lost; type II—when a child leaves after obtaining the guardian’s permission but fails to find their way back to their guardian; and type III—when a guardian and child are separated by the operation of transportation. This study’s findings can assist in the development of environmental design guidelines to prevent children from getting lost.